Method and device for evaluating outlet temperature of combustion chamber of gas turbine in real time and gas turbine

Abstract

The invention relates to the technical field of equipment parameter monitoring, in particular to a gas turbine combustion chamber outlet temperature real-time evaluation method and device and a gas turbine. The method comprises the steps that atmospheric environment parameters, fuel supply parameters, exhaust parameters and unit operation parameters are monitored in real time; on the basis of the first law of thermodynamics, the atmospheric environment parameters and the fuel supply parameters serve as input energy items, the exhaust parameters and the unit operation parameters serve as output energy items, a first evaluation model is constructed, and the air flow of the inlet of the air compressor is predicted in real time through the first evaluation model; based on the compressor inlet air flow, the bleed air proportionality coefficient and the pressure loss coefficient, the combustion chamber outlet pressure is predicted through a second evaluation model; and a third evaluation model is constructed by combining the critical flow state maintained by the throat of the turbine first-stage guide blade, and the combustion chamber outlet pressure is input into the third evaluation model to calculate the combustion chamber outlet temperature. Online evaluation of the outlet temperature of the combustion chamber of the gas turbine can be realized, and the monitoring efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of equipment parameter monitoring technology, and in particular to a method and device for real-time evaluation of the outlet temperature of a gas turbine combustion chamber, and a gas turbine. Background Technology

[0002] The combustor outlet of a gas turbine is typically the location with the highest temperature and pressure in the turbine's flow path. For example, the combustor outlet temperature of an H-class heavy-duty gas turbine can reach over 1800K, and the pressure can exceed 2MPa. Therefore, the combustor outlet temperature is difficult to obtain directly through measurement, both during the gas turbine's development and testing phases. However, the combustor outlet temperature is a critical parameter of the gas turbine's thermodynamic cycle, determining not only its thermal efficiency and power output but also significantly impacting the lifespan of hot-end components such as turbine blades. Therefore, assessing the gas turbine's combustor outlet temperature is essential for the safe, stable, and efficient operation of the gas turbine.

[0003] In related technologies, obtaining the combustion chamber outlet temperature of a gas turbine requires not only accurate acquisition of core compressor parameters and air system data, but also knowledge of fuel supply information and core combustion indicators. Furthermore, based on these parameters, multiple rounds of parameter adjustments and adaptations are needed, taking into account the specific characteristics of core components such as the compressor and combustion chamber. Because the calculation of these parameters and characteristics relies on multi-source offline parameters and complex corrections, real-time online monitoring of the combustion chamber outlet temperature is difficult to achieve. Therefore, this method is also insufficient for obtaining the gas turbine combustion chamber outlet temperature during overall testing and actual operation. In summary, a novel technical solution is urgently needed to address at least one of the aforementioned technical problems. Summary of the Invention

[0004] This application addresses the technical problems existing in the prior art by providing a method and apparatus for real-time evaluation of the combustion chamber outlet temperature of a gas turbine, as well as a gas turbine, to achieve online evaluation of the combustion chamber outlet temperature, which helps to ensure the safe, stable operation and efficient control of the gas turbine.

[0005] In a first aspect, embodiments of this application provide a method for real-time evaluation of the outlet temperature of a gas turbine combustion chamber, the method comprising:

[0006] By deploying sensor systems at the inlet and outlet boundaries of the gas turbine, atmospheric environmental parameters, fuel supply parameters, exhaust parameters, and unit operating parameters are monitored in real time.

[0007] Taking the set area from the compressor inlet to the turbine outlet as the control body in the gas turbine, based on the first law of thermodynamics, atmospheric environmental parameters and fuel supply parameters are used as input energy terms, and exhaust parameters and unit operating parameters are used as output energy terms. The input energy terms and output energy terms are balanced through iterative calculation to construct the first evaluation model. The compressor inlet air flow rate is predicted in real time through the first evaluation model.

[0008] Based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber, the combustion chamber outlet pressure is predicted by the second evaluation model.

[0009] A third evaluation model is constructed by combining the critical flow state maintained at the throat of the first-stage guide vane during gas turbine operation. The combustion chamber outlet pressure is used as input, and the combustion chamber outlet temperature is obtained by inversion reasoning through the third evaluation model.

[0010] Secondly, embodiments of this application provide a real-time evaluation device for the outlet temperature of a gas turbine combustion chamber. This device is applied to a gas turbine and includes the following units, wherein...

[0011] The monitoring unit is configured to monitor atmospheric environmental parameters, fuel supply parameters, exhaust parameters, and unit operating parameters in real time through a sensor system located at the gas turbine inlet and outlet boundaries.

[0012] The first evaluation unit is configured to take the set area from the compressor inlet to the turbine outlet as the control body in the gas turbine. Based on the first law of thermodynamics, it takes atmospheric environmental parameters and fuel supply parameters as input energy terms and exhaust parameters and unit operating parameters as output energy terms. Through iterative calculation, the input energy terms and output energy terms are balanced to construct the first evaluation model. The compressor inlet air flow rate is predicted in real time through the first evaluation model.

[0013] The second evaluation unit is configured to predict the combustion chamber outlet pressure based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber through the second evaluation model.

[0014] The third evaluation unit is configured to construct a third evaluation model by combining the critical flow state maintained by the throat of the first-stage guide vane during the operation of the gas turbine. The combustion chamber outlet pressure is used as input, and the combustion chamber outlet temperature is obtained by inversion reasoning through the third evaluation model.

[0015] Thirdly, embodiments of this application provide a gas turbine, which is equipped with a data monitoring system, the data monitoring system including at least one processor, a memory, and an input / output unit;

[0016] The memory is used to store computer programs, and the processor is used to call the computer programs stored in the memory to execute the first aspect of the gas turbine combustor outlet temperature real-time evaluation method.

[0017] Fourthly, a computer-readable storage medium is provided, including instructions that, when executed on a computer, cause the computer to perform the real-time evaluation method for the gas turbine combustor outlet temperature of the first aspect.

[0018] The beneficial effects of this application are: it provides a method and device for real-time evaluation of the combustion chamber outlet temperature of a gas turbine, and a gas turbine itself. In this technical solution, firstly, a sensor system arranged at the inlet and outlet boundaries of the gas turbine monitors atmospheric environmental parameters, fuel supply parameters, exhaust parameters, and unit operating parameters in real time. Next, taking a set area from the compressor inlet to the turbine outlet as the control volume in the gas turbine, based on the first law of thermodynamics, atmospheric environmental parameters and fuel supply parameters are used as input energy terms, and exhaust parameters and unit operating parameters are used as output energy terms. Through iterative calculation, the input and output energy terms are balanced to construct a first evaluation model. The compressor inlet airflow is then predicted in real time using this first evaluation model. Finally, based on the compressor inlet airflow, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss within the combustion chamber, the combustion chamber outlet pressure is predicted using a second evaluation model. Finally, a third evaluation model is constructed by combining the critical flow state maintained at the throat of the turbine's first-stage guide vane during gas turbine operation. Using the combustion chamber outlet pressure as input, the combustion chamber outlet temperature is obtained through inversion reasoning using this third evaluation model. This technical solution, through conventional operating data directly monitored at the gas turbine inlet and outlet boundaries (such as atmospheric temperature, pressure, humidity, fuel flow rate, exhaust temperature, output torque, and speed), based on the principle of energy conservation and the throttling characteristics of the turbine's first-stage guide vane throat, achieves online evaluation of the gas turbine combustion chamber outlet temperature without relying on the specific characteristic parameters of core components such as the compressor and turbine. This effectively simplifies the evaluation process, significantly reduces its complexity, and avoids dependence on gas turbine component parameters. Furthermore, this technical solution provides crucial data support for real-time monitoring of gas turbine operating status, hot-end component life assessment, performance degradation analysis, and low-emission combustion chamber control, effectively ensuring the safe, stable operation and efficient control of the gas turbine. Attached Figure Description

[0019] Figure 1 This is a flowchart illustrating a method for real-time evaluation of the outlet temperature of a gas turbine combustion chamber according to an embodiment of this application.

[0020] Figure 2 This is a schematic diagram of the structure of a real-time evaluation system for the outlet temperature of a gas turbine combustion chamber according to an embodiment of this application;

[0021] Figure 3 This is a schematic diagram illustrating the principle of a real-time evaluation method for the outlet temperature of a gas turbine combustion chamber according to an embodiment of this application.

[0022] Figure 4 This is a schematic diagram of the structure of a real-time evaluation device for the outlet temperature of a gas turbine combustion chamber according to an embodiment of this application;

[0023] Figure 5 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application.

[0024] Figure 2 In the diagram, the components are: 1. Atmospheric temperature sensor; 2. Atmospheric pressure sensor; 3. Atmospheric humidity sensor; 4. Compressor outlet pressure sensor; 5. Fuel mass flow sensor; 6. Fuel temperature sensor; 7. Exhaust temperature sensor; 8. Gas turbine output torque sensor; 9. Gas turbine speed sensor; 10. Computing system; ① Air; ② Fuel; ③ Exhaust; A. Control unit; a. Compressor; b. Combustion chamber; c. Turbine; d. Load; e. Output shaft. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] In related technologies, the traditional method for calculating the combustion chamber outlet temperature of gas turbines is generally based on the conservation of combustion chamber energy. Measuring the combustion chamber outlet temperature requires not only accurate acquisition of core compressor parameters and air system data, but also knowledge of fuel supply information and core combustion indicators. Furthermore, it necessitates multiple rounds of parameter adjustments and adaptations based on the specific characteristics of core components such as the compressor and combustion chamber. For example, the efficiency characteristics of different compressor models directly affect the air energy calculation results, requiring targeted adjustments to correction coefficients. This deep reliance on the equipment's inherent characteristics leads to an exceptionally complex calculation process, requiring the integration of multi-source component data and the establishment of complex correlation models. Moreover, unseen characteristic parameters are easily affected by factors such as equipment wear and operating condition fluctuations, and traditional methods struggle to dynamically correct these deviations in real time, significantly reducing the accuracy and reliability of the calculation results. Because the calculation process relies on multi-source offline parameters and complex corrections, it is difficult to achieve real-time online monitoring of the combustion chamber outlet temperature, further hindering technicians from accurately obtaining core temperature data of the equipment's core components during gas turbine testing and actual operation. Furthermore, the existing technologies struggle to achieve real-time online monitoring of the combustion chamber outlet temperature. This makes it impossible to dynamically assess the real-time heat load and lifespan degradation of hot-end components such as turbine blades, and also hinders precise control over combustion efficiency and pollutant generation patterns in low-emission combustion chambers. Consequently, the optimization of gas turbine operation, fault prediction, and lifespan management lack core data support. Therefore, a novel technical solution is urgently needed to address at least one of the aforementioned technical problems.

[0027] To address at least one technical problem in the prior art, this application provides a method and apparatus for real-time evaluation of the combustion chamber outlet temperature of a gas turbine, as well as a gas turbine itself. The core principle of the technical solution provided by this application lies in achieving online estimation of the combustion chamber outlet temperature by real-time monitoring of conventional parameters at the gas turbine inlet and outlet boundaries, combined with thermodynamic laws and flow characteristics, without relying on detailed characteristic curves of components such as the compressor or turbine.

[0028] Specifically, the core bottleneck of traditional methods lies in the need to obtain precise characteristic curves of components such as the compressor and turbine (e.g., the relationship between compressor efficiency and flow rate and speed). These curves are not only difficult to obtain accurately, but also dynamically change with equipment aging and operating condition fluctuations, resulting in an unstable foundation for the calculation model. The core principle of the embodiments in this application is to treat the entire region from the gas turbine compressor to the turbine outlet as a unified black box control body. This method does not concern itself with the detailed working process of each component inside the control body (e.g., how the compressor compresses air), but focuses on the energy and mass conservation relationship that can be directly measured at the boundary of the control body. By monitoring the energy difference between the inlet (air, fuel) and the outlet (exhaust, shaft work), the internal air flow rate can be directly deduced. This method transforms the complex component characteristic problem into an overall energy balance problem based on universal physical laws (the first law of thermodynamics), fundamentally eliminating the dependence on the characteristics of specific equipment or specific component models, and improving the versatility and robustness of the method.

[0029] On the other hand, traditional methods require several internal parameters, such as compressor efficiency and combustion efficiency, which are difficult to obtain accurately in real time. This application simplifies the parameter requirements to the most common and easily monitored physical quantities at the gas turbine inlet and outlet boundaries, such as ambient temperature, humidity, pressure, fuel flow rate, temperature, exhaust temperature, output torque, and speed. These parameters can be directly and continuously acquired using mature industrial sensors, ensuring reliable and real-time data. For the few remaining empirical parameters (such as the combustion chamber pressure drop coefficient and air bleed ratio), this method sets them to fixed values ​​based on extensive engineering experience or stable values ​​obtainable after system calibration, rather than dynamic variables requiring frequent adjustments. This parameter simplification strategy enables real-time online calculations, eliminating the need for offline testing or complex data fitting.

[0030] On the other hand, after obtaining the combustion chamber outlet pressure, traditional approaches may still rely on the turbine's expansion characteristics. This application's embodiment cleverly utilizes the critical flow phenomenon at the throat of the turbine's first-stage guide vane. When the gas turbine operates near its rated conditions, the flow velocity at this throat reaches the speed of sound, creating a throttling and blocking effect. Under this critical state, the mass flow rate of the gas flowing through the throat is directly proportional to the total pressure at the combustion chamber outlet and inversely proportional to the square root of the total outlet temperature, with the coefficients in the equation determined by the throat area (fixed geometric dimensions) and the gas properties. Therefore, this method constructs a constraint equation, using the combustion chamber outlet pressure and flow rate calculated in previous steps as known quantities, and the combustion chamber outlet temperature as an unknown quantity, and then solving iteratively through this critical flow equation. This step transforms the temperature assessment problem into a mathematical problem under strong constraints; the principle is clear, the calculation is efficient, and it is very suitable for real-time computation.

[0031] In summary, a complete solution was constructed through a three-core architecture: replacing component characteristics with overall energy balance, replacing complex internal parameters with conventional boundary parameters, and inverting temperature based on critical flow principles. This transforms a traditional problem—relying on multi-source offline data, involving complex models, and being difficult to implement—into an online evaluation process that relies solely on real-time monitoring data, features a simple model, and enables rapid computation. This effectively solves the challenge of real-time monitoring and provides crucial real-time data support for the life assessment, performance optimization, and precise emission control of gas turbine hot-end components.

[0032] The real-time evaluation scheme for the gas turbine combustor outlet temperature provided in this application embodiment can also be executed by an electronic device, such as a server, server cluster, or cloud server. This electronic device can also be a terminal device such as a mobile phone, computer, tablet computer, wearable device, or dedicated device (such as a dedicated terminal device with a real-time evaluation method system for gas turbine combustor outlet temperature). These electronic devices can also incorporate the chips described in the above embodiments. Alternatively, these electronic devices can also install a service program for executing the real-time evaluation scheme for the gas turbine combustor outlet temperature.

[0033] Figure 1 A flowchart illustrating a method for real-time evaluation of gas turbine combustor outlet temperature provided in this application embodiment is shown below. Figure 1 As shown, the method includes the following steps:

[0034] 101. Through a sensor system deployed at the inlet and outlet boundaries of the gas turbine, atmospheric environmental parameters, fuel supply parameters, exhaust parameters, and unit operating parameters are monitored in real time.

[0035] 102. Taking the set area from the compressor inlet to the turbine outlet as the control body in the gas turbine, based on the first law of thermodynamics, atmospheric environmental parameters and fuel supply parameters are used as input energy terms, and exhaust parameters and unit operating parameters are used as output energy terms. The input energy terms and output energy terms are balanced through iterative calculation to construct the first evaluation model. The compressor inlet air flow rate is predicted in real time through the first evaluation model.

[0036] 103. Based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber, the combustion chamber outlet pressure is predicted by the second evaluation model.

[0037] 104. A third evaluation model is constructed by combining the critical flow state maintained at the throat of the first-stage guide vane during the operation of the gas turbine. The combustion chamber outlet pressure is used as input, and the combustion chamber outlet temperature is obtained by inversion reasoning through the third evaluation model.

[0038] Through steps 101 to 104 above, firstly, atmospheric environmental parameters (such as atmospheric temperature, pressure, and humidity), fuel supply parameters (such as fuel flow rate, temperature, and composition), exhaust parameters (such as exhaust temperature), and unit operating parameters (such as output torque and speed) are collected in real time using a sensor network deployed in the gas turbine system. Taking the area from the compressor inlet to the turbine outlet as the control volume, based on the first law of thermodynamics, the energy carried in by the inlet air and fuel is used as the input, and the energy carried out by the exhaust and the mechanical work output by the unit are used as the output. Through iterative calculation, the assumed value of the compressor inlet air flow rate is adjusted to balance the input and output energy, thereby predicting the compressor inlet air flow rate in real time. The key to this step is to indirectly derive the internal flow rate using conventional monitoring parameters, avoiding the difficulty of direct measurement. Next, based on the compressor inlet air flow rate obtained above, combined with the known fuel flow rate and composition, the combustion chamber inlet flow rate is calculated. It is necessary to consider the air system bleed ratio, i.e., a portion of the compressor outlet air is bleeded away for cooling or other purposes; this ratio is usually determined based on experience or calibration tests. Then, based on the fuel and air mixture, the composition and physical properties of the combustion chamber outlet gas, such as the gas constant, are calculated. Simultaneously, using data measured by the compressor outlet pressure sensor and combined with the combustion chamber pressure loss coefficient (which characterizes the flow loss inside the combustion chamber and is usually an empirical value), the combustion chamber outlet pressure is calculated. This step correlates flow rate with pressure, providing a basis for temperature assessment. Finally, the characteristic of the turbine first-stage guide vane throat maintaining a critical flow state during gas turbine operation is utilized. When the turbine reaches a critical state, the gas flow velocity remains at the speed of sound, and throttling and blockage occur at the throat. At this point, the flow rate satisfies a specific relationship with pressure, temperature, and throat area. Based on the combustion chamber outlet pressure, combustion chamber outlet flow rate, gas constant, and turbine first-stage guide vane throat area (a fixed value), the specific heat ratio of the gas (related to composition and temperature) is calculated by iteratively assuming a combustion chamber outlet temperature, making the flow equation valid, thereby inversely deducing the combustion chamber outlet temperature. This step utilizes the critical flow at the turbine throat, converting pressure parameters into temperature parameters, enabling real-time assessment.

[0039] It is worth noting that all calculations involved in the embodiments of this application are based on the International System of Units (SI), with an enthalpy reference temperature of 15°C, ensuring data consistency. The technical solution provided by this application overcomes the limitations of traditional methods that require component characteristics and a large number of parameters, achieving real-time monitoring of the combustion chamber outlet temperature through only routine boundary tests, thus providing an effective means for gas turbine performance optimization and life assessment.

[0040] For example, with Figure 2Taking the real-time evaluation system for the combustion chamber outlet temperature of a gas turbine as an example, the system includes a load (d), a control unit A, a real-time monitoring system for the gas turbine, and a computing system (10). The inputs of the system include air ① and fuel ②, and the output of the system is exhaust gas ③. The control unit A includes a compressor (a), a combustion chamber (b), a turbine (c), and an output shaft (e). The real-time monitoring system for the gas turbine includes the following components: an atmospheric temperature sensor (1), an atmospheric pressure sensor (2), an atmospheric humidity sensor (3), a compressor outlet pressure sensor (4), a fuel mass flow sensor (5), a fuel temperature sensor (6), an exhaust gas temperature sensor (7), a gas turbine output torque sensor (8), and a gas turbine speed sensor (9). The computing system (10) can be used to implement the data processing flow of steps 101 to 104 in the embodiments of this application.

[0041] Step 101: The atmospheric environment parameters, fuel supply parameters, exhaust parameters, and unit operating parameters are monitored in real time by a sensor system deployed at the inlet and outlet boundaries of the gas turbine.

[0042] In this embodiment, to achieve real-time assessment of the gas turbine combustion chamber outlet temperature, a sensor system deployed at key nodes of the gas turbine was first constructed. This system comprehensively covers the entire flow path boundary of the unit from the air inlet to the exhaust outlet, and can continuously and synchronously collect various physical parameters necessary for operation.

[0043] For example, the sensor network is specifically arranged as follows: At the air inlet of the gas turbine, atmospheric temperature, atmospheric pressure, and atmospheric humidity sensors are installed to monitor the atmospheric environmental conditions before the gas enters the compressor. A pressure sensor is installed on the compressor outlet pipe to measure the compressed air pressure. A fuel mass flow sensor and a fuel temperature sensor are installed on the fuel supply line to monitor the fuel supply status. An exhaust temperature sensor is installed in the exhaust section of the gas turbine to measure the temperature of the gas after power is applied. For the unit's operating status, core mechanical power parameters are obtained through gas turbine output torque and gas turbine speed sensors installed on the output shaft system.

[0044] The parameters monitored by the aforementioned sensor system can be categorized into four main types based on their physical meaning and function. The first type is atmospheric environmental parameters, which reflect the physical state of the air entering the gas turbine. The second type is fuel supply parameters, reflecting the characteristics of the main energy source input into the unit. The third type is exhaust parameters, characterizing the thermodynamic state of the working fluid after it expands and does work in the turbine. The fourth type is unit operating parameters, directly reflecting the mechanical work output by the gas turbine and its rotational speed.

[0045] Atmospheric environmental parameters define the initial physical state of the air entering the gas turbine and serve as the baseline for overall energy balance calculations. These parameters are acquired through sensors deployed at the gas turbine inlet boundary and specifically include atmospheric temperature, atmospheric pressure, and atmospheric humidity. These parameters directly determine the density, specific heat capacity, and other physical properties of the air at the compressor inlet, thus affecting its enthalpy. In the evaluation process described below, these parameters are used to calculate the enthalpy of the inlet air and are key input variables for iteratively solving the compressor inlet air flow rate. Changes in the atmospheric environment directly affect the performance of the gas turbine; therefore, real-time monitoring of these parameters ensures that the evaluation model can adapt to the external conditions of unit operation.

[0046] Fuel supply parameters characterize the primary energy source input into the gas turbine and form the basis for energy release calculations in the combustion chamber. These parameters are measured by sensors installed on the fuel supply line and mainly include fuel mass flow rate and fuel temperature. Furthermore, the fuel's chemical composition, as a known inherent property, is also important input information. Fuel mass flow rate directly reflects the amount of energy input into the combustion system per unit time, while fuel temperature is used to calculate the sensible heat carried by the fuel as it enters the system. Combined with the fuel's lower heating value, these parameters work together to determine the total energy released during combustion, providing core data for subsequent flow rate and temperature calculations based on energy conservation.

[0047] Exhaust parameters characterize the thermodynamic state of the working fluid after it expands and does work in the turbine, representing the outlet conditions after a gas turbine completes one thermodynamic cycle. Among these parameters, the system currently primarily monitors exhaust temperature. Exhaust temperature sensors are typically installed in the turbine exhaust cylinder or flue. Exhaust temperature is a crucial indicator of the overall thermal efficiency of the gas turbine and a key parameter in the energy balance calculation, the first step in the evaluation algorithm. By measuring the exhaust temperature, the enthalpy of the exhaust working fluid can be calculated. This enthalpy, along with the inlet air enthalpy, input fuel energy, and output work, constitutes a closed-loop control volume energy equation, used to inversely deduce the compressor inlet air flow rate, which cannot be directly measured.

[0048] The operating parameters of the gas turbine directly reflect its output performance as a prime mover and are a direct measure of its ability to perform external work. These parameters include the turbine's output torque and rotational speed. Torque and speed sensors are typically mounted on the gas turbine's output shaft. The product of these two parameters is directly proportional to the gas turbine's output power. In the energy conservation equation of the evaluation algorithm, the mechanical work output by the unit is an important energy output term, and its magnitude directly affects the iterative calculation results of the compressor inlet airflow. Real-time monitoring of these parameters ensures that the evaluation model can accurately account for the impact of actual load changes on the internal thermodynamic parameters of the gas turbine.

[0049] In summary, these parameters together constitute a complete monitoring system, covering the entire thermodynamic process from energy input (fuel parameters), initial state of the working medium (atmospheric parameters), to energy output (unit operating parameters) and final emissions (exhaust parameters). These parameters are all conventional physical quantities that can be directly and in real-time measured during gas turbine operation, ensuring that the assessment method for combustion chamber outlet temperature can be implemented without relying on the characteristic curves of internal gas turbine components (such as compressors and turbines).

[0050] by Figure 2 Taking the real-time evaluation system for the gas turbine combustor outlet temperature shown as an example, in step 101, the atmospheric temperature (T0), atmospheric pressure (P0), atmospheric humidity (W), compressor outlet pressure (P3), and fuel flow rate (m³) can be obtained through the gas turbine real-time monitoring system. f ), fuel temperature (T) 30 ), exhaust temperature (T6), gas turbine output torque (T), gas turbine speed (N).

[0051] Step 102: Taking the set area from the compressor inlet to the turbine outlet as the control body in the gas turbine, based on the first law of thermodynamics, atmospheric environmental parameters and fuel supply parameters are used as input energy terms, and exhaust parameters and unit operating parameters are used as output energy terms. Through iterative calculation, the input energy terms and output energy terms are balanced to construct the first evaluation model. The compressor inlet air flow rate is predicted in real time through the first evaluation model.

[0052] In this embodiment, the control body is a specific and well-defined physical space within the gas turbine. This physical space encloses the core heat-to-work conversion components of the gas turbine, facilitating the systematic analysis of energy changes in the working fluid (air and gas) flowing through this space.

[0053] For example, in energy conservation analysis, a key physical model is defined for the control volume of the gas turbine, defined as the region from the compressor inlet to the turbine outlet. The inlet boundary of this control volume is located at the compressor inlet, through which ambient air enters. The outlet boundary is located at the turbine outlet, through which the high-temperature combustion gas, after work, is discharged. The physical walls of the control volume consist of the outer shells of components such as the compressor, combustion chamber, and turbine; these walls are designed to be fixed and thermally adiabatic. The control volume includes the core components of the gas turbine that enable heat-to-work conversion: the compressor compresses air, the combustion chamber mixes and burns fuel and air to release heat energy, and the turbine expands the high-temperature, high-pressure combustion gas to perform work. The control volume explicitly excludes loads (such as generators) and the intake and exhaust piping systems; the output shaft is considered the path for transmitting mechanical work, and its output work is treated as an energy term passing through the control volume boundaries.

[0054] Understandably, choosing this region as the control volume is fundamentally aimed at establishing a simplified model that does not rely on the characteristics of internal gas turbine components. This choice is rationalized on two points: First, this region ensures the integrity of the energy conversion process; the core compression, combustion, and expansion processes of the gas turbine all occur completely within this control volume, providing a solid foundation for applying the law of conservation of energy. Second, this region achieves the measurability of boundary parameters; all energy inputs and outputs of the control volume strictly correspond to conventional parameters that can be directly and in real-time monitored during gas turbine operation. Specifically, input energy includes the energy carried by the air entering through the inlet boundary (whose state is described by atmospheric environmental parameters) and the chemical energy carried by the fuel injected through the fuel supply system (whose characteristics are described by fuel supply parameters); output energy includes the thermal energy carried by the exhaust gas discharged through the outlet boundary (whose state is described by exhaust parameters) and the mechanical work transferred to the external load through the output shaft (directly reflected by unit operating parameters). This control system avoids dependence on complex internal characteristics such as compressor efficiency and turbine efficiency. It only uses measurable parameters at the inlet and outlet boundaries to iteratively solve the key intermediate variable, namely the compressor inlet air flow rate, through the energy conservation equation, thus providing an analytical basis for real-time and accurate assessment of the combustion chamber outlet temperature.

[0055] As an optional embodiment, in step 102, when constructing the first evaluation model, the enthalpy of the compressor inlet air is calculated based on the atmospheric temperature, atmospheric pressure, and atmospheric humidity parameters; the sensible heat of the fuel inlet and the lower heating value of the fuel are calculated based on the fuel temperature and fuel composition parameters; the shaft work output is calculated based on the gas turbine speed and gas turbine output torque parameters; an initial value for the compressor inlet air flow rate is set, and the exhaust composition is calculated in conjunction with the fuel flow rate parameters; and the exhaust enthalpy is calculated based on the exhaust temperature parameters; an energy balance formula is constructed. The process includes an input energy term comprising air input energy calculated from the compressor inlet air flow rate and inlet air enthalpy, and fuel input energy calculated from fuel flow rate, fuel inlet sensible heat, fuel lower heating value, and combustion efficiency. The output energy term comprises exhaust output energy calculated from exhaust mass flow rate and exhaust enthalpy determined by the compressor inlet air flow rate and fuel flow rate, and work output calculated from shaft work output. By iteratively adjusting the compressor inlet air flow rate, the energy balance equation is made valid, and a first evaluation model is constructed based on the energy balance equation to predict the compressor inlet air flow rate in real time.

[0056] In this embodiment of the application, the first evaluation model is a calculation model based on the overall structure of the gas turbine and the principle of energy conservation, which uses an iterative algorithm to solve for the compressor inlet air flow in real time.

[0057] Continue with Figure 2 Taking the real-time evaluation system for the gas turbine combustor outlet temperature shown as an example, assuming that the following parameters are obtained through the gas turbine real-time monitoring system in step 101: atmospheric temperature (T0), atmospheric pressure (P0), atmospheric humidity (W), compressor outlet pressure (P3), and fuel flow rate (m³ / s). f ), fuel temperature (T) 30 ), exhaust temperature (T6), gas turbine output torque (T), gas turbine speed (N).

[0058] Based on the above parameters, firstly, using atmospheric temperature (T0), atmospheric pressure (P0), and atmospheric humidity (W) from the atmospheric environmental parameters, and combining this with the air composition in the equipment operating environment, the enthalpy (h1) of the compressor inlet air is calculated using the working fluid thermophysical property calculation formula. All enthalpy calculations are based on a common reference temperature (e.g., 15°C).

[0059] Furthermore, based on the fuel temperature (T) in the fuel supply parameters... 30 ), fuel composition, and calculation of fuel inlet sensible heat (h) 30 Sensible heat is the physical enthalpy, which is the temperature of the fuel from a reference temperature (e.g., 15°C) to its lowest heating value (LHV). The sensible heat is the temperature of the fuel as it heats from its base temperature (e.g., 15°C) to its highest heating value (T). 30 The physical enthalpy change of a component is primarily determined by the weighted contribution of its specific heat capacity.

[0060] For example, calculating the sensible heat of the fuel inlet (h 30 When preparing fuel for combustion, the first step is to clearly define the specific composition of the fuel components and determine the mass fraction of each component (the sum of the mass fractions of all components must equal 1). Simultaneously, the reference temperature is set to atmospheric temperature (T0), with 15℃ as the default unless otherwise specified. Next, based on the fuel's physical state (gaseous or liquid), the pure components are queried for temperatures ranging from T0 to the fuel temperature (T...). 30 The average isobaric specific heat capacity (cp) within the range i For gaseous fuels, the isobaric specific heat capacity of the gaseous components must be selected, while for liquid fuels, the isobaric specific heat capacity of the liquid components must be used. Finally, the mass fraction (w) of each component is calculated. i Average isobaric specific heat capacity (cp) i ) and temperature difference (i.e., T) 30 Multiply the difference between T0 and T0, and then sum the calculation results for all components to obtain the total value, which is the sensible heat h at the fuel inlet. 30 .

[0061] The lower heating value of a fuel refers to the heat released when water vapor in the combustion products exists in gaseous form after the fuel is completely burned. Its value is determined only by the types and proportions of fuel components and is independent of physical conditions such as temperature.

[0062] For example, before calculation, it's necessary to confirm the proportions of each fuel component. If the mass fraction is already known, it can be used directly. If only the mole fraction is known, it needs to be converted using the molar mass of the component. The conversion method is to multiply the mole fraction of each component by its corresponding molar mass, add the results, and then divide this sum by the result of multiplying the mole fraction of each component by its molar mass to obtain the mass fraction of the corresponding component. Next, the lower heating value (LCV) of each pure component needs to be looked up to ensure that the unit of this value matches the mass fraction. Finally, the mass fraction of each component is multiplied by the LHC of its corresponding component, and the products of all components are summed. The final sum is the LHC of the fuel.

[0063] Next, the product of the gas turbine speed (N) and the gas turbine output torque (T) in the unit operating parameters is taken as the shaft power output (NT).

[0064] Based on the above assumptions, further assume that the compressor inlet air flow rate is m a Based on this, the compressor inlet air flow rate and fuel flow rate (m³ / s) can be used as a reference. f Calculate the exhaust composition, and based on the exhaust composition and exhaust temperature (T6), calculate the exhaust enthalpy (h6). Simultaneously, ensure the energy balance equation holds, and iteratively calculate the compressor inlet air flow rate (m³ / s). a Specifically, the compressor inlet air flow rate (m) is set. a The initial value is used to calculate the exhaust composition by combining the fuel flow rate in the fuel supply parameters, and the exhaust enthalpy (h6) is calculated based on the exhaust temperature (T6) in the exhaust parameters.

[0065] Furthermore, an energy balance equation is constructed, wherein the input energy term includes air input energy calculated from the compressor inlet air flow rate and inlet air enthalpy, fuel input energy calculated from fuel flow rate, fuel inlet sensible heat, fuel lower heating value, and combustion efficiency, and the output energy term includes exhaust output energy calculated from the exhaust mass flow rate determined by the compressor inlet air flow rate and fuel flow rate and exhaust enthalpy, and work output calculated from shaft work output (NT). Further optionally, the energy balance equation in step 102 is: the product of the compressor inlet air flow rate and the difference between exhaust enthalpy and inlet air enthalpy equals the product of fuel flow rate and fuel inlet sensible heat, fuel lower heating value, and combustion efficiency minus the exhaust enthalpy, and then minus the shaft work output.

[0066] Finally, by iteratively adjusting the compressor inlet air flow rate, the energy balance equation is made valid, and the first evaluation model is constructed based on the energy balance equation to predict the compressor inlet air flow rate in real time.

[0067] For example, based on the aforementioned example parameters, let's continue to assume that the compressor inlet flow rate is m. a The first evaluation model calculates the compressor inlet flow rate m.a The process can be represented by the following formula: Where, m f For fuel flow rate, h 30 Where LHV is the sensible heat of the fuel inlet, h6 is the lower heating value of the fuel, and T is the total enthalpy of the gas turbine exhaust. N is the gas turbine speed; for example, for a heavy-duty gas turbine used in power generation, N can be set to 50 r / s. η is the combustion efficiency, an empirical parameter, which can be selected as 99.9%.

[0068] As an optional embodiment, in step 102, when the compressor inlet air flow rate is predicted in real time by the first evaluation model, an initial value of the compressor inlet air flow rate is set; based on the initial value of the compressor inlet air flow rate and the fuel flow rate in the fuel supply parameters, the exhaust composition is calculated; based on the exhaust composition and the exhaust temperature in the exhaust parameters, the exhaust enthalpy is calculated; the initial value of the compressor inlet air flow rate, the inlet air enthalpy, the fuel flow rate, the sensible heat of the fuel inlet, the lower heating value of the fuel, the combustion efficiency, the exhaust enthalpy, and the shaft work output are substituted into the energy balance equation to calculate the first difference between the left and right sides of the energy balance equation; it is determined whether the first difference is less than a first preset tolerance; if the first difference is not less than the first preset tolerance, the compressor inlet air flow rate is adjusted, and the steps of calculating the exhaust composition, exhaust enthalpy, and the first difference are repeated until the first difference is less than the first preset tolerance, and the compressor inlet air flow rate obtained by iterative calculation is used as the real-time output value of the first evaluation model. For example, m a The new value is compared with the old value. If the difference does not reach the preset convergence criterion, the new value is used as the guess value for the next iteration, and the above calculation steps are repeated until the calculated value of m in two consecutive iterations is obtained. a If the value is sufficiently close, the energy balance equation is considered to hold, and the iteration converges. The resulting m... a This refers to the real-time predicted airflow at the compressor inlet under the current operating conditions.

[0069] Step 103: Based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber, the combustion chamber outlet pressure is predicted by the second evaluation model.

[0070] As an optional embodiment, in step 103, based on the compressor inlet air flow rate, the actual air flow rate entering the combustion chamber is determined by introducing a bleed air ratio coefficient characterizing the distribution of the working fluid between the compressor and the combustion chamber, thus obtaining the combustion chamber inlet air flow rate. In this embodiment, the bleed air ratio coefficient characterizing the distribution of the working fluid between the compressor and the combustion chamber is used. Here, the bleed air ratio coefficient is the bleed air ratio of the air system, which can be an empirical parameter or obtained from air system calibration tests.

[0071] Further optionally, the combustion chamber inlet air flow rate is the product of the difference obtained by subtracting the bleed air proportioning coefficient and the compressor inlet air flow rate. This step can be expressed as the following formula: m 31 =(1-α)m a ; where m 31 The inlet air flow rate of the combustion chamber is α, the bleed air proportionality coefficient is m a This refers to the air flow rate at the compressor inlet.

[0072] Furthermore, in step 103, based on the principle of mass conservation, the air flow rate at the combustion chamber inlet is integrated with the fuel flow rate in the fuel supply parameters to evaluate and obtain the combustion chamber outlet gas flow rate and the corresponding gas composition.

[0073] Further optionally, the combustion chamber outlet gas flow rate is the sum of the combustion chamber inlet air flow rate and the fuel flow rate. This step can be expressed by the following formula: m4 = m f +m 31 ; where m 31 The airflow rate at the combustion chamber inlet, m f m is the fuel flow rate, and m4 is the combustion chamber outlet gas flow rate.

[0074] Finally, in step 103, based on the real-time collected compressor outlet pressure, the combustion chamber outlet pressure is predicted by introducing a pressure loss coefficient characterizing the internal flow loss of the combustion chamber. Optionally, the compressor outlet pressure is obtained in real-time by a pressure sensor located at the gas turbine compressor outlet. In this embodiment, the pressure loss coefficient characterizes the internal flow loss of the combustion chamber. For example, the pressure loss coefficient is the combustion chamber pressure loss coefficient, which is an empirical parameter and can be selected as 5%.

[0075] Further optionally, the combustion chamber outlet pressure is the product of the difference obtained by subtracting the pressure loss coefficient and the compressor outlet pressure. This step can be expressed as the following formula: P4 = (1-β)P3; where P4 is the combustion chamber outlet pressure, β is the pressure loss coefficient, and P3 is the compressor outlet pressure.

[0076] Step 104: A third evaluation model is constructed by combining the critical flow state maintained at the throat of the first-stage guide vane during the operation of the gas turbine. The combustion chamber outlet pressure is used as input, and the combustion chamber outlet temperature is obtained by inversion reasoning through the third evaluation model.

[0077] Understandably, the throttling phenomenon at the throat of the turbine's first-stage guide vane is the core physical principle for achieving real-time assessment of the combustion chamber outlet temperature. This phenomenon involves the core airflow path of the gas turbine. The turbine's first-stage guide vane is a stationary component located behind the combustion chamber outlet and before the first-stage turbine blades. Its blade passage is designed with a converging shape, with the narrowest point defined as the throat. When high-temperature, high-pressure gas flows out of the combustion chamber and passes through this converging passage, the airflow velocity increases significantly. Under normal operating conditions of the gas turbine, this acceleration effect causes the gas to reach the local speed of sound at the throat, i.e., the critical flow state where Mach number equals 1. At this point, the flow enters a throttling or blocked state. This means that the gas velocity reaches its maximum value at the throat, and the mass flow rate through the throat also reaches its limit under the current upstream gas conditions. The resulting important physical effect is that downstream pressure fluctuations cannot propagate upstream at the speed of sound and therefore cannot affect the upstream flow conditions. Thus, the upstream flow state is limited to depend only on the total pressure and total temperature at the combustion chamber outlet, and is independent of changes in back pressure behind the turbine.

[0078] This flow-locked state establishes a key deterministic relationship. Given the throat's geometric area, the mass flow rate through the throat uniquely depends on the total pressure and total temperature at the combustion chamber outlet. This application utilizes this relationship in reverse. Specifically, the actual mass flow rate through the throat and the combustion chamber outlet pressure are first indirectly obtained through calculations such as the conservation of overall engine energy. Under these conditions, the combustion chamber outlet temperature, which is normally difficult to measure directly, becomes the only solution satisfying this critical flow relationship.

[0079] The essence of the throttling phenomenon is to provide a reliable physical law constraint that allows the system to avoid dependence on the characteristics of complex components such as compressors and turbines. The combustion chamber outlet temperature, located at the high temperature and high pressure core, can be accurately calculated using only relatively easily measurable conventional parameters of the gas turbine boundary, thus achieving a significant technological breakthrough.

[0080] It is understandable that Figure 3 The diagram visually illustrates the core physical phenomenon upon which step 104 is based by demonstrating the relationship between the relative reduced flow rate and the expansion ratio. The horizontal axis, expansion ratio, reflects the pressure driving force propelling the gas through the guide vane, while the vertical axis, relative reduced flow rate, characterizes the actual flow capacity. Figure 3The curves for different operating parameters all exhibit the same evolution pattern. In the initial stage with a small expansion ratio, the flow rate increases rapidly and linearly with increasing pressure drive; at this point, the flow is in a subcritical state, and changes in downstream back pressure directly affect the upstream flow. When the expansion ratio increases to the critical point, the flow velocity at the throat of the guide reaches the local speed of sound, and the flow enters a critical state. After this point, the curve shows a significant plateau characteristic, indicating that even if the expansion ratio continues to increase, the flow rate remains constant, and the flow enters a choking state. This horizontal segment means that the throat velocity continues to maintain the speed of sound, the mass flow rate reaches its maximum value, and a typical throttling phenomenon is formed.

[0081] Furthermore, Figure 3 The revealed characteristics of the clogging state directly correspond to the implementation principle of step 104. Within the plateau region, the relative reduced flow rate remains constant, verifying that the mass flow rate under critical conditions depends only on the total pressure and temperature at the combustion chamber outlet. This flow state lock-in effect provides the theoretical basis for the inversion calculation in step 104. The actual mass flow rate and combustion chamber outlet pressure obtained through the aforementioned steps have a definite mathematical correlation with the combustion chamber outlet temperature under clogging conditions. The characteristic that the curves under different operating conditions in the graph eventually converge to the same upper flow limit further proves the robustness of this physical relationship under a wide range of operating conditions, ensuring the reliability of the method described in step 104 in practical applications. Therefore, Figure 3 The process of constructing a mathematical bridge using the critical flow law in step 104 was visualized, and the physical mechanism of inverting the core temperature parameters through conventional parameters was elucidated.

[0082] In an optional embodiment of step 104, a flow equation under critical flow conditions is derived based on the combustion chamber outlet pressure, combustion chamber outlet gas flow rate, gas constant, and the throat area of ​​the turbine first-stage guide vane. This flow equation is derived from the principle that the gas velocity at the turbine first-stage guide vane throat remains constant at the speed of sound under critical flow conditions, and that the throat is throttled and blocked. Furthermore, an initial assumed value for the combustion chamber outlet temperature is set, and the specific heat ratio of the gas is calculated based on the gas composition corresponding to the combustion chamber outlet gas flow rate. The specific heat ratio is obtained through a curve showing the relationship between gas composition and temperature or a thermodynamic database. Further optionally, the specific heat ratio is set to 1.33 in the initial evaluation. For example, the gas composition includes at least one of the following: carbon dioxide, water vapor, and nitrogen.

[0083] Next, the combustion chamber outlet pressure, combustion chamber outlet gas flow rate, gas constant, turbine first-stage guide vane throat area, and calculated gas specific heat ratio are substituted into the flow equation to obtain the calculated value of the combustion chamber outlet temperature. For example, the process of obtaining the combustion chamber outlet temperature can be expressed as the following formula: Where T4 is the combustion chamber outlet temperature, k is the specific heat ratio of the fuel gas, A is the throat area of ​​the turbine first-stage guide vane, P4 is the combustion chamber outlet pressure, R is the fuel gas constant, and m4 is the combustion chamber outlet flow rate. This equation is derived from the mass flow rate formula under critical flow conditions.

[0084] Finally, a second difference is compared between the calculated value and the initial assumed value to determine whether the second difference is less than a second preset tolerance. If the second difference is not less than the second preset tolerance, the initial assumed value of the combustion chamber outlet temperature is adjusted, and the steps of calculating the specific heat ratio of the gas, the calculated value of the combustion chamber outlet temperature, and the second difference are repeated until the second difference is less than the second preset tolerance. The combustion chamber outlet temperature obtained by iterative calculation is then used as the real-time output value of the third evaluation model.

[0085] In this embodiment, conventional operating data directly monitored at the gas turbine inlet and outlet boundaries, based on the principle of energy conservation and the throttling characteristics of the turbine's first-stage guide vane throat, enables online assessment of the gas turbine combustor outlet temperature without relying on the specific characteristic parameters of core components such as the compressor and turbine. This effectively simplifies the assessment process, significantly reduces its complexity, and avoids dependence on gas turbine component parameters. Furthermore, this technical solution provides crucial data support for real-time monitoring of gas turbine operating status, hot-end component life assessment, performance degradation analysis, and low-emission combustor control, effectively ensuring the safe, stable operation and efficient control of the gas turbine.

[0086] This application eliminates the reliance on characteristic curves of components such as compressors and turbines in traditional methods. Traditional methods require obtaining complex parameters such as compressor efficiency, flow characteristics, and turbine expansion efficiency under different operating conditions. These data are often difficult to obtain accurately or drift with equipment aging. As mentioned above, this application only needs to utilize conventional sensor data deployed at the gas turbine inlet and outlet boundaries (including atmospheric temperature, atmospheric pressure, atmospheric humidity, compressor outlet pressure, fuel flow and temperature, exhaust temperature, output torque, and speed). Through the established control volume energy conservation model (i.e., the first evaluation model) and the critical flow model based on throat throttling phenomenon (i.e., the third evaluation model), real-time, online calculation of the combustion chamber outlet temperature can be achieved, thereby improving the condition monitoring and performance analysis of the gas turbine. The combustion chamber outlet temperature is one of the most critical parameters characterizing the integrity and efficiency of the gas turbine thermodynamic cycle. Continuous monitoring allows operators to detect potential issues. For example, if the calculated combustion chamber outlet temperature shows a trend of increasing after maintaining the same fuel quantity and water washing cycle, it may indicate that compressor blade fouling or wear is causing a decrease in compression efficiency. This provides a direct basis for scheduling online or offline water washing and predictive maintenance. Real-time combustion chamber outlet temperature data can be linked with macroscopic parameters such as power and efficiency for analysis, accurately assessing fluctuations in overall machine performance caused by factors such as changes in environmental conditions and component aging. This provides refined data support for the economic dispatch and energy efficiency management of power plants. In the development of new gas turbine models or the optimization and improvement testing of existing models, the embodiments of this application can provide a macroscopic characterization of the combustion chamber outlet temperature field that is difficult to obtain by traditional methods. This can be used to verify whether the design goals have been achieved and guide further optimization and adjustment of design parameters.

[0087] Furthermore, embodiments of this application can also achieve life assessment and health status diagnosis of hot-end components. The service life of hot-end components such as gas turbine blades depends heavily on the temperature levels they withstand. Excessively high temperatures drastically accelerate material creep, oxidation, and thermal fatigue damage, which are primary factors limiting the overhaul cycle and service life of the entire engine. Embodiments of this application provide crucial input for the life management of hot-end components and the diagnosis of the overall engine health status by real-time assessment of the combustion chamber outlet temperature.

[0088] Specifically, the calculated combustion chamber outlet temperature directly reflects the gas temperature level at the turbine inlet and is a direct indicator for assessing the instantaneous heat load on the blades. By setting a temperature alarm threshold, overheating caused by control system malfunctions or combustion instability can be effectively avoided, preventing irreversible damage to the turbine blades. Combining material life-temperature curves (such as the Larson-Miller parametric method) with real-time monitored temperature data and operating time allows for precise calculation of the cumulative lifespan loss of critical components such as turbine blades. This makes it possible to shift from traditional time-based maintenance to more scientific condition-based maintenance, avoiding waste caused by over-maintenance and preventing serious accidents caused by the exhaustion of lifespan. Abnormal fluctuations or deviations from design values ​​in the combustion chamber outlet temperature are often early signs of combustion system failures (such as fuel nozzle blockage or flame tube cracks), cooling system failures (such as blockage of cooling air passages), or damage to hot-channel components. Intelligent analysis of temperature trends can provide early warning of faults, offering decision support for scheduling planned shutdowns for maintenance and preventing unplanned shutdowns and serious accidents.

[0089] Furthermore, the embodiments of this application can realize the judgment and optimized control of the low-emission combustor's operating state. Modern low-emission combustors (such as dry-type low-NOx burners) achieve minimized NOx emissions by precisely controlling the fuel-air mixing ratio and combustion zone temperature. The combustor outlet temperature is a key comprehensive parameter for measuring the temperature distribution and maximum flame temperature throughout the combustor, and the flame temperature directly determines the generation rate of thermal NOx. The combustor outlet temperature evaluated in real time in the embodiments of this application can serve as an indicator for judging whether the low-emission combustion mode is in the ideal operating window. If the temperature deviates from the design optimal range, it may indicate problems such as uneven fuel / air mixing, improper switching of staged combustion modes, or combustion oscillations, leading to excessive emissions or decreased combustion efficiency. The embodiments of this application can feed this temperature signal back to the gas turbine control system, forming a closed loop with control loops such as fuel quantity, compressor guide vane angle, and staged fuel distribution valve. The control system can dynamically fine-tune the fuel-air mixing ratio based on the real-time temperature, ensuring that the combustor always operates in the optimal range of low emissions and high efficiency. This is crucial for gas turbines to maintain stable low emissions under complex operating conditions such as frequent load changes and fluctuating fuel composition. The embodiments of this application achieve real-time monitoring and optimized control of the combustion chamber outlet temperature, ensuring that the gas turbine consistently meets increasingly stringent environmental emission standards, avoiding fines or operational restrictions due to excessive emissions. Simultaneously, optimized combustion conditions also help improve combustion efficiency and reduce fuel consumption, achieving both environmental and economic benefits.

[0090] In summary, the embodiments of this application not only provide a novel method for real-time evaluation of the combustion chamber outlet temperature of a gas turbine, but also further realize refined and intelligent operation and maintenance of the gas turbine in multiple dimensions such as performance monitoring, life management, and emission control through the acquisition of this key parameter.

[0091] In another embodiment of this application, a real-time assessment device for the outlet temperature of a gas turbine combustor is also provided. See also Figure 4 The device is applied to a gas turbine, and the device includes the following units:

[0092] The monitoring unit is configured to monitor atmospheric environmental parameters, fuel supply parameters, exhaust parameters, and unit operating parameters in real time through a sensor system located at the gas turbine inlet and outlet boundaries.

[0093] The first evaluation unit is configured to take the set area from the compressor inlet to the turbine outlet as the control body in the gas turbine. Based on the first law of thermodynamics, it takes atmospheric environmental parameters and fuel supply parameters as input energy terms and exhaust parameters and unit operating parameters as output energy terms. Through iterative calculation, the input energy terms and output energy terms are balanced to construct the first evaluation model. The compressor inlet air flow rate is predicted in real time through the first evaluation model.

[0094] The second evaluation unit is configured to predict the combustion chamber outlet pressure based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber through the second evaluation model.

[0095] The third evaluation unit is configured to construct a third evaluation model by combining the critical flow state maintained by the throat of the first-stage guide vane during the operation of the gas turbine. The combustion chamber outlet pressure is used as input, and the combustion chamber outlet temperature is obtained by inversion reasoning through the third evaluation model.

[0096] Optionally, the first evaluation unit, taking the set area from the compressor inlet to the turbine outlet as the control body in the gas turbine, uses atmospheric environmental parameters and fuel supply parameters as input energy terms, and exhaust parameters and unit operating parameters as output energy terms, based on the first law of thermodynamics. Through iterative calculation, the input and output energy terms are balanced to construct the first evaluation model, which is configured to: calculate the enthalpy of the compressor inlet air based on atmospheric temperature, atmospheric pressure, and atmospheric humidity in the atmospheric environmental parameters; calculate the sensible heat of the fuel inlet and the lower heating value of the fuel based on the fuel temperature and fuel composition in the fuel supply parameters; calculate the shaft work output based on the gas turbine speed and gas turbine output torque in the unit operating parameters; and set the initial value of the compressor inlet air flow rate. Starting from the initial value, and combining the fuel flow rate in the fuel supply parameters, the exhaust composition is calculated, and the exhaust enthalpy is calculated based on the exhaust temperature in the exhaust parameters. An energy balance equation is constructed, where the input energy term includes the air input energy calculated from the compressor inlet air flow rate and the inlet air enthalpy, the fuel input energy calculated from the fuel flow rate, the fuel inlet sensible heat, the fuel lower heating value, and the combustion efficiency, and the output energy term includes the exhaust output energy calculated from the exhaust mass flow rate and the exhaust enthalpy determined by the compressor inlet air flow rate and the fuel flow rate, and the work output calculated from the shaft work output. By iteratively adjusting the compressor inlet air flow rate, the energy balance equation is made valid, and a first evaluation model is constructed based on the energy balance equation to predict the compressor inlet air flow rate in real time.

[0097] Further optionally, the energy balance equation is: the product of the compressor inlet air flow rate and the difference between the exhaust enthalpy and the inlet air enthalpy is equal to the product of the fuel flow rate and the fuel inlet sensible heat, the fuel lower heating value and the combustion efficiency minus the exhaust enthalpy, and then minus the shaft work output.

[0098] Optionally, the first evaluation unit, which predicts the compressor inlet air flow rate in real time using the first evaluation model, is configured to: set an initial value for the compressor inlet air flow rate; calculate the exhaust composition based on the initial value of the compressor inlet air flow rate and the fuel flow rate in the fuel supply parameters; calculate the exhaust enthalpy based on the exhaust composition and the exhaust temperature in the exhaust parameters; substitute the initial value of the compressor inlet air flow rate, the inlet air enthalpy, the fuel flow rate, the sensible heat of the fuel inlet, the lower heating value of the fuel, the combustion efficiency, the exhaust enthalpy, and the shaft work output into the energy balance equation to calculate a first difference between the left and right sides of the energy balance equation; determine whether the first difference is less than a first preset tolerance; if the first difference is not less than the first preset tolerance, adjust the compressor inlet air flow rate, repeat the steps of calculating the exhaust composition, exhaust enthalpy, and the first difference until the first difference is less than the first preset tolerance, and use the compressor inlet air flow rate obtained by iterative calculation as the real-time output value of the first evaluation model.

[0099] Optionally, the second evaluation unit, based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber, predicts the combustion chamber outlet pressure through a second evaluation model. This is configured as follows: based on the compressor inlet air flow rate, by introducing the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, the actual air flow rate entering the combustion chamber is determined to obtain the combustion chamber inlet air flow rate; based on the principle of mass conservation, the combustion chamber inlet air flow rate is fused with the fuel flow rate in the fuel supply parameters to evaluate and obtain the combustion chamber outlet gas flow rate and corresponding gas composition; based on the real-time collected compressor outlet pressure, by introducing the pressure loss coefficient characterizing the internal flow loss of the combustion chamber, the combustion chamber outlet pressure is predicted.

[0100] Alternatively, the compressor outlet pressure can be obtained in real time by a pressure sensor located at the outlet of the gas turbine compressor.

[0101] Further optionally, the combustion chamber inlet air flow rate is the product of the difference obtained by subtracting the bleed air ratio coefficient and the compressor inlet air flow rate; the combustion chamber outlet gas flow rate is the sum of the combustion chamber inlet air flow rate and the fuel flow rate; and the combustion chamber outlet pressure is the product of the difference obtained by subtracting the pressure loss coefficient and the compressor outlet pressure.

[0102] Optionally, the third evaluation unit constructs a third evaluation model based on the critical flow state maintained by the turbine first-stage guide vane throat during gas turbine operation. Using the combustion chamber outlet pressure as input, the third evaluation model is used for inverse reasoning to obtain the combustion chamber outlet temperature. This model is configured as follows: based on the combustion chamber outlet pressure, combustion chamber outlet gas flow rate, gas constant, and turbine first-stage guide vane throat area, the flow equation under critical flow conditions is derived from the principle that the gas velocity at the turbine first-stage guide vane throat remains constant under critical flow conditions, and that the throat is throttled and blocked. An initial assumed value for the combustion chamber outlet temperature is set based on the gas composition corresponding to the combustion chamber outlet gas flow rate. The specific heat ratio of the combustion chamber is calculated. The combustion chamber outlet pressure, combustion chamber outlet gas flow rate, gas constant, turbine first-stage guide vane throat area, and the calculated specific heat ratio of the combustion chamber are substituted into the flow equation to obtain the calculated value of the combustion chamber outlet temperature. The second difference between the calculated value and the initial assumed value is compared. It is determined whether the second difference is less than the second preset tolerance. If the second difference is not less than the second preset tolerance, the initial assumed value of the combustion chamber outlet temperature is adjusted, and the steps of calculating the specific heat ratio of the combustion chamber, the calculated value of the combustion chamber outlet temperature, and the second difference are repeated until the second difference is less than the second preset tolerance. The combustion chamber outlet temperature obtained by iterative calculation is used as the real-time output value of the third evaluation model.

[0103] The device can implement various steps in the above method embodiments, which will not be elaborated here.

[0104] In this embodiment, a real-time assessment device for the gas turbine combustor outlet temperature is employed. This device can directly monitor conventional operating data from the gas turbine inlet and outlet boundaries. Based on the principle of energy conservation and the throttling characteristics of the turbine's first-stage guide vane throat, it achieves real-time assessment of the gas turbine combustor outlet temperature without relying on the specific characteristic parameters of core components such as the compressor and turbine. This simplifies the assessment process, reduces its complexity, and avoids dependence on gas turbine component parameters. Furthermore, this embodiment provides crucial data support for real-time monitoring of gas turbine operating status, hot-end component life assessment, performance degradation analysis, and low-emission combustor control, effectively ensuring the safe, stable operation and efficient control of the gas turbine.

[0105] This application provides a gas turbine equipped with a data monitoring system, which includes at least one processor, a memory, and an input / output unit. The memory stores a computer program, and the processor invokes the stored program to execute the real-time gas turbine combustor outlet temperature evaluation method described in the above-described method embodiments. For example, the data monitoring system can be implemented as an electronic device. Please refer to [link to relevant documentation]. Figure 5, Figure 5 A schematic diagram illustrating an embodiment of the electronic device provided in this application. For example... Figure 5 As shown, this application provides an electronic device 500, including a memory 510, a processor 520, and a software program 511 stored in the memory 510 and executable on the processor 520. When the processor 520 executes the software program 511, it implements the various steps in the above embodiments.

[0106] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0107] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for real-time evaluation of the outlet temperature of a gas turbine combustion chamber, characterized in that, The method includes: By deploying sensor systems at the inlet and outlet boundaries of the gas turbine, atmospheric environmental parameters, fuel supply parameters, exhaust parameters, and unit operating parameters are monitored in real time. Taking the set area from the compressor inlet to the turbine outlet as the control body in the gas turbine, based on the first law of thermodynamics, atmospheric environmental parameters and fuel supply parameters are used as input energy terms, and exhaust parameters and unit operating parameters are used as output energy terms. The input energy terms and output energy terms are balanced through iterative calculation to construct the first evaluation model. The compressor inlet air flow rate is predicted in real time through the first evaluation model. Based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber, the combustion chamber outlet pressure is predicted by the second evaluation model. A third evaluation model is constructed by combining the critical flow state maintained at the throat of the first-stage guide vane during gas turbine operation. The combustion chamber outlet pressure is used as input, and the combustion chamber outlet temperature is obtained by inversion reasoning through the third evaluation model.

2. The method for real-time evaluation of gas turbine combustion chamber outlet temperature according to claim 1, characterized in that, The control unit in the gas turbine is defined as the area from the compressor inlet to the turbine outlet. Based on the first law of thermodynamics, atmospheric environmental parameters and fuel supply parameters are used as input energy terms, and exhaust parameters and unit operating parameters are used as output energy terms. Through iterative calculations, the input and output energy terms are balanced to construct the first evaluation model, which includes: Calculate the enthalpy of the air at the compressor inlet based on atmospheric environmental parameters such as atmospheric temperature, atmospheric pressure, and atmospheric humidity. Calculate the sensible heat of the fuel inlet and the lower heating value of the fuel based on the fuel temperature and fuel composition in the fuel supply parameters; Calculate shaft power output based on the gas turbine speed and gas turbine output torque in the unit's operating parameters; Set the initial value of the compressor inlet air flow rate, combine it with the fuel flow rate in the fuel supply parameters, calculate the exhaust composition, and calculate the exhaust enthalpy value based on the exhaust temperature in the exhaust parameters. An energy balance equation is constructed, in which the input energy term includes the air input energy calculated from the compressor inlet air flow rate and the inlet air enthalpy, the fuel input energy calculated from the fuel flow rate, the fuel inlet sensible heat, the fuel lower heating value and the combustion efficiency, and the output energy term includes the exhaust output energy calculated from the exhaust mass flow rate and exhaust enthalpy determined by the compressor inlet air flow rate and the fuel flow rate, and the work output calculated from the shaft work output. By iteratively adjusting the compressor inlet air flow rate, the energy balance equation is made valid, and a first evaluation model is constructed based on the energy balance equation to predict the compressor inlet air flow rate in real time.

3. The method for real-time evaluation of gas turbine combustion chamber outlet temperature according to claim 2, characterized in that, The energy balance equation is: the product of the compressor inlet air flow rate and the difference between the exhaust enthalpy and the inlet air enthalpy is equal to the product of the fuel flow rate and the sensible heat of the fuel inlet, the lower heating value of the fuel, and the combustion efficiency, minus the exhaust enthalpy, and then minus the shaft work output.

4. The method for real-time evaluation of gas turbine combustion chamber outlet temperature according to claim 2, characterized in that, The step of predicting the compressor inlet air flow rate in real time using the first evaluation model includes: Set the initial value for the compressor inlet air flow rate; Based on the initial value of the compressor inlet air flow rate and the fuel flow rate in the fuel supply parameters, calculate the exhaust composition; Calculate the exhaust enthalpy based on the exhaust composition and the exhaust temperature in the exhaust parameters; Substitute the initial value of the compressor inlet air flow rate, the inlet air enthalpy, the fuel flow rate, the fuel inlet sensible heat, the fuel lower heating value, the combustion efficiency, the exhaust enthalpy, and the shaft power output into the energy balance equation to calculate the first difference between the left and right sides of the energy balance equation. Determine whether the first difference is less than the first preset tolerance; If the first difference is not less than the first preset tolerance, the compressor inlet air flow rate is adjusted, and the steps of calculating the exhaust components, exhaust enthalpy and the first difference are repeated until the first difference is less than the first preset tolerance. The compressor inlet air flow rate obtained by iterative calculation is used as the real-time output value of the first evaluation model.

5. The method for real-time evaluation of gas turbine combustion chamber outlet temperature according to claim 1, characterized in that, The combustion chamber outlet pressure is predicted using a second evaluation model based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber. This includes: Based on the compressor inlet air flow rate, the actual air flow rate entering the combustion chamber is determined by introducing the bleed air ratio coefficient, which characterizes the distribution of working fluid between the compressor and the combustion chamber, and the combustion chamber inlet air flow rate is obtained. Based on the principle of mass conservation, the combustion chamber inlet air flow rate and the fuel flow rate in the fuel supply parameters are integrated to evaluate and obtain the combustion chamber outlet gas flow rate and the corresponding gas composition. Based on the real-time collected compressor outlet pressure, the combustion chamber outlet pressure is predicted by introducing a pressure loss coefficient that characterizes the internal flow loss of the combustion chamber.

6. The method for real-time evaluation of gas turbine combustion chamber outlet temperature according to claim 5, characterized in that, The compressor outlet pressure is obtained in real time by a pressure sensor located at the outlet of the gas turbine compressor.

7. The method for real-time evaluation of gas turbine combustion chamber outlet temperature according to claim 5, characterized in that, The combustion chamber inlet air flow rate is the product of the difference obtained by subtracting the bleed air ratio coefficient and the compressor inlet air flow rate. The combustion chamber outlet gas flow rate is the sum of the combustion chamber inlet air flow rate and the fuel flow rate. The combustion chamber outlet pressure is the product of the difference obtained by subtracting the pressure loss coefficient and the compressor outlet pressure.

8. The method for real-time evaluation of gas turbine combustion chamber outlet temperature according to claim 1, characterized in that, The third evaluation model is constructed by combining the critical flow state maintained at the throat of the first-stage guide vane during gas turbine operation. Using the combustion chamber outlet pressure as input, the combustion chamber outlet temperature is obtained through inversion reasoning using the third evaluation model, including: Based on the combustion chamber outlet pressure, combustion chamber outlet gas flow rate, gas constant, and the throat area of ​​the turbine first-stage guide vane, the flow equation under critical flow conditions is derived. The flow equation is derived based on the principle that the gas velocity at the throat of the turbine first-stage guide vane remains constant at the speed of sound under critical flow conditions, and that the throat is throttled and blocked. Set an initial assumed value for the combustion chamber outlet temperature, and calculate the specific heat ratio of the gas based on the gas composition corresponding to the gas flow rate at the combustion chamber outlet; Substitute the combustion chamber outlet pressure, combustion chamber outlet gas flow rate, gas constant, turbine first-stage guide vane throat area, and calculated gas specific heat ratio into the flow equation to obtain the calculated value of the combustion chamber outlet temperature. Compare the calculated value with the initial assumed value using a second difference; Determine whether the second difference is less than the second preset tolerance; If the second difference is not less than the second preset tolerance, the initial assumed value of the combustion chamber outlet temperature is adjusted, and the steps of calculating the specific heat ratio of the gas, the calculated value of the combustion chamber outlet temperature, and the second difference are repeated until the second difference is less than the second preset tolerance. The combustion chamber outlet temperature obtained by iterative calculation is then used as the real-time output value of the third evaluation model.

9. A real-time evaluation device for the outlet temperature of a gas turbine combustion chamber, characterized in that, The device is applied to a gas turbine, and the device includes the following units, wherein... The monitoring unit is configured to monitor atmospheric environmental parameters, fuel supply parameters, exhaust parameters, and unit operating parameters in real time through a sensor system located at the gas turbine inlet and outlet boundaries. The first evaluation unit is configured to take the set area from the compressor inlet to the turbine outlet as the control body in the gas turbine. Based on the first law of thermodynamics, it takes atmospheric environmental parameters and fuel supply parameters as input energy terms and exhaust parameters and unit operating parameters as output energy terms. Through iterative calculation, the input energy terms and output energy terms are balanced to construct the first evaluation model. The compressor inlet air flow rate is predicted in real time through the first evaluation model. The second evaluation unit is configured to predict the combustion chamber outlet pressure based on the compressor inlet air flow rate, the bleed air ratio coefficient characterizing the working fluid distribution between the compressor and the combustion chamber, and the pressure loss coefficient characterizing the internal flow loss of the combustion chamber through the second evaluation model. The third evaluation unit is configured to construct a third evaluation model by combining the critical flow state maintained by the throat of the first-stage guide vane during the operation of the gas turbine. The combustion chamber outlet pressure is used as input, and the combustion chamber outlet temperature is obtained by inversion reasoning through the third evaluation model.

10. A gas turbine, characterized in that, The gas turbine is equipped with a data monitoring system, which includes: a memory for storing computer software programs; and a processor for reading and executing the computer software programs, thereby realizing the real-time evaluation method for the gas turbine combustion chamber outlet temperature as described in any one of claims 1-8.

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