A method for constructing a starting performance model for marine gas turbine engines

Abstract

This invention provides a method for building a startup performance model for a marine gas turbine engine. First, a calculation model for the aerothermodynamic performance of the gas turbine engine is created using C++. Then, a heat transfer model, temperature sensor model, and control law model for the gas turbine engine's high-temperature components are created using M language. Then, based on test data from the startup process of the gas turbine engine, the pressure ratio of representative components of the gas turbine engine and the efficiency change law with the physical rotation speed of the gas generator during the startup process are analyzed to generate and correct the corresponding low-speed characteristics of the gas turbine engine's rotating components, thereby achieving a highly accurate real-time simulation of the startup performance of the gas turbine engine. This method takes into account the heat exchange between the high-temperature gas and the external atmosphere and the gas turbine engine itself, thereby improving the accuracy of the simulation of the gas turbine engine's performance during the startup process and providing a simulation test tool for the design and optimization of the startup control law of the gas turbine engine.

Description

[Technical Field]

[0001] The present invention relates to the technical field of gas turbine engine performance simulation, and particularly to a method for constructing a starting performance model of a marine gas turbine engine. [Background technology]

[0002] Marine gas turbine engines have the advantages of high power, small size, light weight, efficient starting, good acceleration and maneuverability, which can effectively improve the tactical and technical performance of ships and significantly increase their sailing speed and maneuverability. Surface starting is the first stage of gas turbine engine operation and is a prerequisite for a smooth transition to normal operation.

[0003] High-precision simulation methods for the start-up process of marine gas turbine engines, both domestic and international, have not been fully studied, especially the impact of different atmospheric temperatures and initial wall temperatures on start-up performance. The lack of consideration of the heat exchange between the hot gas and the gas turbine engine itself and the heat exchange between the gas turbine engine itself and the external environment during the start-up process results in poor simulation accuracy for gas turbine engine start-up performance models. The mathematical model construction process for gas turbine engine start-up requires the development of sufficient heat transfer models, temperature sensor models, and control law models. This can significantly improve the performance simulation accuracy of gas turbine engine start-up processes, optimize the gas turbine engine start-up control law for different atmospheric conditions and different initial wall temperatures, shorten start-up times, and improve start-up performance.

[0004] Based on this invention, researchers can create a highly accurate dynamic real-time model and control law model of the gas turbine engine starting process, and comprehensively analyze and evaluate various gas turbine engine starting control laws, thereby shortening the gas turbine engine development cycle to a certain extent, saving development funds and reducing risks. Summary of the Invention [Problem to be solved by the invention]

[0005] The objective of this invention is to develop a starting performance model for a marine gas turbine engine based on the principles of aerothermodynamics, taking into account the heat exchange between the hot gas and the gas turbine engine body during the starting process and the dynamic characteristics of sensors. First, the aerothermodynamic model of the gas turbine engine is developed using C++, and a heat transfer model, temperature sensor model, and control law model of the gas turbine engine's high-temperature components are developed using M language. Then, based on test data from the gas turbine engine's starting process, the pressure ratio of representative components of the gas turbine engine during the starting process and the efficiency change law with the physical rotation speed of the gas generator are analyzed to generate and correct the corresponding low-speed characteristics of the gas turbine engine's rotating components, thereby achieving a highly accurate dynamic real-time simulation of the gas turbine engine's starting performance. [Means for solving the problem]

[0006] Technical Solutions: In order to achieve the above objectives, the technical solutions adopted by the present invention are as follows:

[0007] A method for constructing a starting performance model of a marine gas turbine engine, comprising: Step S1: acquiring measurement parameters of the starting performance of the gas turbine engine, analyzing the inlet total temperature and outlet total temperature, and the inlet total pressure and the outlet total pressure of the compressor and the power turbine, and generating low rotation speed characteristics of the rotating parts in the starting process of the gas turbine engine by a characteristic identification method, wherein the measurement parameters include the inlet total temperature and outlet total temperature, the inlet total pressure and the outlet total pressure, and the fuel flow rate of the compressor and the power turbine, the output power of the power turbine, and the rotation speeds of the rotors of the gas turbine and the power turbine, and the time required for the rotation speed of the rotor of the gas turbine to reach a predetermined value is the starting time, and the rotating parts include the compressor, the gas turbine, and the power turbine; Step S2: creating a component-level starting mathematical model of the gas turbine engine, constructing the power and torque characteristics of the starter based on the conventional design parameters of the starter, and calculating the power consumption of a compressor and the output power of a gas turbine in the starting process of the gas turbine engine, wherein the components include a starter, an air intake system, a compressor, a combustion chamber, a gas turbine, a power turbine, and an exhaust system of the gas turbine engine; Step S3: constructing a heat transfer model and a temperature sensor model of a high-temperature component of the gas turbine engine and evaluating an influence of heat exchange between the high-temperature gas and the high-temperature component on the starting performance of the gas turbine engine, the high-temperature component including the combustion chamber, the gas turbine, and the power turbine; Step S4 of constructing an open-loop control law model and a closed-loop control law model in a starting process of the gas turbine engine, wherein the open-loop starting control law includes a relationship between a gas turbine corrected rotation speed and a fuel supply amount and a relationship between the gas turbine corrected rotation speed and a fuel-air ratio, and the closed-loop starting control law includes a relationship between the gas turbine corrected rotation speed and an acceleration of a rotor of the gas turbine; and Step S5 of simulating performance of the gas turbine engine in a start-up process under various initial atmospheric conditions, where the various initial conditions include various atmospheric temperatures, various atmospheric pressures, and various initial wall temperatures.

[0008] Preferably, in step S1, when a certain type of marine gas turbine engine is subjected to a sea surface start-up test, the acceleration of the gas turbine rotor is calculated from the rotational speed of the gas turbine rotor during the start-up process, and then combined with a rotor dynamics equation to estimate the residual power of the gas turbine rotor at various times during the start-up process, and then combined with the inlet total temperature and outlet total temperature, inlet total pressure and outlet total pressure of the compressor and power turbine during the start-up process to identify the pressure ratios and efficiency operating characteristic lines of the rotating parts corresponding to different corrected rotational speeds.

[0009] Preferably, the rotor dynamic equation is: TIFF2025540772000002.tif96166TIFF2025540772000003.tif20166.

[0010] Preferably, TIFF2025540772000004.tif70166TIFF2025540772000005.tif39166TIFF2025540772000006.tif58166

[0011] Preferably, TIFF2025540772000007.tif58166TIFF2025540772000008.tif39166TIFF2025540772000009.tif58166

[0012] Preferably, in step S5, The performance of the gas turbine engine during the start-up process is simulated under three atmospheric conditions, where the atmospheric temperature and atmospheric pressure are -15°C and 100,740 Pa, 0°C and 100,570 Pa, and 15°C and 100,020 Pa, respectively. The initial wall temperatures of the combustion chamber, the gas turbine, and the power turbine are set to 15°C for cold start-up, and 60°C, 90°C, and 120°C for hot start-up, respectively. [Effects of the Invention]

[0013] Benefits: This invention provides a method for building a model of the starting performance of a marine gas turbine engine. This method is based on the principles of aerothermodynamics and takes into account the heat exchange between the hot gas and the gas turbine engine body during the starting process and the dynamic characteristics of sensors. First, a gas turbine engine aerothermodynamic performance model is built using C++. Then, a heat transfer model, temperature sensor model, and control law model for the high-temperature components of the gas turbine engine are built using M language. Finally, based on the starting test data of the gas turbine engine, the pressure ratio of representative components of the gas turbine engine during the starting process and the efficiency change law with the physical rotation speed of the gas generator are analyzed to generate and correct the corresponding low-speed characteristics of the rotating components of the gas turbine engine, thereby achieving a highly accurate real-time simulation of the starting performance of the gas turbine engine. The present invention improves the accuracy of simulation of the performance of a gas turbine engine during the start-up process by creating a heat transfer model and a temperature sensor model of the high-temperature components of the gas turbine engine, taking into account the heat exchange between the high-temperature gas, the atmosphere of the external environment, and the gas turbine engine body. This can be used to create an integrated simulation platform for starting up the gas turbine engine, which can simulate the closed-loop control of the start-up process of the gas turbine engine, and can provide a simulation test tool for designing and optimizing the start-up control law of the gas turbine engine. [Brief explanation of the drawings]

[0014] [Figure 1] 3 is a flowchart of a method for constructing a starting performance model of a marine gas turbine engine according to the present invention. [Figure 2] 1A and 1B are characteristic diagrams of the compressor boost ratio and efficiency during the startup process, respectively, obtained by the characteristic identification method of the present invention; [Figure 3]1A and 1B are characteristic diagrams of the expansion ratio and efficiency of a gas turbine during a start-up process, respectively, obtained by the characteristic identification method according to the present invention; [Figure 4] 1A and 1B are characteristic diagrams of the expansion ratio and efficiency of a power turbine during a start-up process, respectively, obtained by the characteristic identification method according to the present invention; [Figure 5] FIG. 2 is a torque characteristic diagram of a starter for a gas turbine engine according to the present invention. [Figure 6] FIG. 2 is a power characteristic diagram of a starter for a gas turbine engine according to the present invention. [Figure 7] 1 is a schematic diagram of a heat transfer model of a gas turbine of a gas turbine engine according to the present invention; [Figure 8] 4 is a simulation curve of the rotational speed of a gas turbine when the gas turbine engine is started at different ambient temperatures before ignition according to the present invention; [Figure 9] 1A and 1B are graphs showing the change in the gas turbine speed when the gas turbine engine is started at various atmospheric temperatures according to the present invention, respectively. FIG. 1B shows the change in the power turbine inlet total temperature when the gas turbine engine is started at various atmospheric temperatures according to the present invention. [Figure 10] 1 is an open loop fuel air ratio control law when a gas turbine engine is started in accordance with the present invention. [Figure 11] 1A is a graph showing the change in gas turbine speed when the gas turbine engine is started with open-loop fuel supply and various initial wall temperatures according to the present invention; and FIG. 1B is a graph showing the change in power turbine inlet total temperature when the gas turbine engine is started with open-loop fuel supply and various initial wall temperatures according to the present invention. [Figure 12]1A is a graph showing the change in the rotational speed of a gas turbine when the gas turbine engine is supplied with fuel in a closed loop at various initial wall temperatures according to the present invention; and FIG. 1B is a graph showing the change in the inlet total temperature of a power turbine when the gas turbine engine is started with fuel supplied in a closed loop at various initial wall temperatures according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] In order to clarify the objectives, technical solutions and advantages of the embodiments of the present invention, the present invention will be described more clearly and completely below with reference to the drawings. The described embodiments are only a part of the embodiments of the present invention and do not cover all the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without any creative work fall within the protection scope of the present invention.

[0016] The present invention provides a method for constructing a starting performance model of a marine gas turbine engine, the specific flow of which is shown in FIG.

[0017] First, a C++-based calculation method for the aero-thermodynamics of a gas turbine engine is established, and the test data of the gas turbine engine's start-up process is analyzed to generate characteristic diagrams of the pressure ratio and efficiency of representative components of the gas turbine engine when they start up and work together. Then, a gas turbine engine component-level model based on the M language is constructed. Specifically, it is as follows:

[0018] Step S1: Obtain test data on the starting performance of a gas turbine engine and analyze the inlet and outlet parameters of representative components of the gas turbine engine, where the test data includes the total temperature and total pressure at the inlet and outlet of the components, and the representative components include a compressor and a power turbine. A characteristic identification method is used to generate low-speed characteristics of rotating components, including the compressor, gas turbine, and power turbine, during the starting process of the gas turbine engine. As a result of the characteristic identification method, the compressor boost ratio characteristic is shown in Figure 2a, the compressor efficiency characteristic is shown in Figure 2b, the gas turbine expansion ratio characteristic is shown in Figure 3a, the gas turbine efficiency characteristic is shown in Figure 3b, the power turbine expansion ratio characteristic is shown in Figure 4a, and the power turbine efficiency characteristic is shown in Figure 4b.

[0019] Step S2: Create a component-level mathematical model of the gas turbine engine starting, construct the power and torque characteristics of the starter based on the traditional design parameters of the starter, and calculate the compressor power consumption and gas turbine output power during the starting process of the gas turbine engine. The components include the starter, air intake, compressor, combustion chamber, gas turbine, power turbine, and exhaust system. The torque characteristics of the starter are shown in Figure 5, and the power characteristics of the starter are shown in Figure 6.

[0020] Step S3: Build a heat transfer model and a temperature sensor model of the high-temperature components of the gas turbine engine, and evaluate the influence of heat exchange between the high-temperature gas and the high-temperature components on the starting performance of the gas turbine engine. The high-temperature components here include the combustion chamber, the gas turbine, and the power turbine. Here, taking the gas turbine as an example, a schematic diagram of the heat transfer of the components is shown in Figure 7.

[0021] Step S4: Establish an open-loop control law model and a closed-loop control law model for the gas turbine engine startup process. The open-loop startup control law includes the relationship between the gas turbine corrected speed and the fuel supply amount, i.e., providing various fuel amounts according to changes in the gas turbine corrected speed during the operation process, and the relationship between the gas turbine corrected speed and the fuel-air ratio, i.e., providing various fuel amounts according to changes in the ratio of the fuel amount to the compressor outlet total pressure during the operation process. The closed-loop startup control law refers to the relationship between the gas turbine corrected speed and the gas turbine rotor acceleration, i.e., adjusting the fuel amount at the next time point by the controller according to a preset gas turbine acceleration command, using the gas turbine rotor acceleration at the previous time point as feedback, and further controlling the gas turbine rotor acceleration process. The performance of the gas turbine engine startup process is simulated under various initial atmospheric conditions. The various initial conditions here include various atmospheric temperatures, various atmospheric pressures, and various initial wall temperatures of the hot parts of the gas turbine engine. According to each of the open-loop control law and the closed-loop control law of the start-up process, performance simulations are performed in the start-up process at various atmospheric temperatures, various atmospheric pressures, and various initial wall temperatures.

[0022] In order to ensure the effectiveness of the model construction method for the starting model of a marine gas turbine engine based on the modular simulation platform designed by the present invention, a specific example for simulating the starting performance model of a certain type of marine gas turbine engine is provided below.

[0023] For the gas turbine engine, the model was simulated up to a specific gas turbine physical speed with initial ambient temperatures of -30°C, 0°C, and 30°C. The gas turbine's physical ignition speed was taken as the 100% reference value, and the simulation curves of gas turbine speed at various ambient temperatures before ignition were obtained (Figure 8). Figure 8 shows that when the gas turbine engine reaches the same ignition physical speed during the startup process, the higher the ambient temperature, the shorter the startup acceleration time. The higher the ambient temperature, the higher the shaft mechanical efficiency, the greater the rotor acceleration, and the shorter the time to reach the ignition speed. Furthermore, under the same open-loop fuel supply law, the model was used to simulate the idling state when ambient temperatures of -30°C, 0°C, and 30°C were given. Key parameters, such as the change curve of gas turbine speed, are shown in Figure 9a, and the change curve of the power turbine inlet total temperature in Figure 9b. It was found that when the ambient temperature was -30°C, the ignition time was earlier than when it was 0°C or 30°C, and that the lower the ambient temperature, the earlier the ignition time. The gas turbine engine modeled in this study ignites and supplies fuel when the corrected speed reaches a certain value. Therefore, according to the corrected speed calculation formula, the lower the ambient temperature, the lower the physical speed corresponding to the corrected speed at ignition. Therefore, when the temperature is low, the corrected speed corresponding to ignition can be reached in advance at a relatively low physical speed. In addition, this simulation used a startup open-loop fuel-air ratio control law (Figure 10) for fuel supply. In cold weather, the gas turbine reaches the corrected speed in advance and supplies fuel earlier, which allows the gas turbine speed to increase more quickly when the ambient temperature is low.

[0024] Given the corrected gas turbine speed and fuel-air ratio, cold and hot starts of a gas turbine engine are simulated. Figure 11a shows the change in gas turbine speed for open-loop fuel supply start-up at various initial wall temperatures. Figure 11b shows the simulated curves of the main performance parameters of a gas turbine engine when starting with open-loop fuel supply at initial wall temperatures T0 of 25°C, 50°C, and 75°C, respectively. It was found that, even with other conditions remaining the same, the change in gas turbine speed during start-up varies with the initial wall temperature. Here, when the wall temperature is higher than the ambient air temperature, the gas turbine engine experiences a hot start, and the gas turbine speed increases relatively quickly. When the wall temperature is equal to the ambient air temperature, the gas turbine engine experiences a cold start, and the gas turbine speed increases relatively slowly. Therefore, when the wall temperature is high and the engine is in a hot start state, most of the heat generated by fuel combustion is used to accelerate the gas turbine rotor, allowing the gas turbine engine to reach ignition speed more quickly and shortening the start-up time.

[0025] Compared with the open-loop fuel supply method, we simulated the startup performance of a gas turbine engine using a closed-loop fuel supply method based on the relationship between gas turbine speed and rotor acceleration, with initial wall temperatures of 25°C, 50°C, and 75°C. The simulation results show the change in gas turbine speed when starting a gas turbine engine with closed-loop fuel supply at various initial wall temperatures (Figure 12a). Figure 12b shows the change in power turbine inlet total temperature when starting a gas turbine engine with closed-loop fuel supply at various initial wall temperatures. As shown in Figure 12a, when fuel is supplied according to the closed-loop control method for gas turbine speed and rotor acceleration, the difference in the change in gas turbine speed under the three different operating conditions is not as obvious as when fuel is supplied according to the open-loop startup control method (Figure 11a). When the initial wall temperature of the gas turbine engine is high, the gas turbine speed reaches the ignition speed and idle speed sooner, but the overall difference is not very clear. As shown in Fig. 12b, when the gas turbine engine is fueled with the rotor acceleration rate of the closed-loop gas turbine at different initial wall temperatures, there is no significant difference in the inlet total temperature of the power turbine, and in this case, the gas turbine engine can obtain almost the same starting acceleration performance.

[0026] The above is only a preferred embodiment of the present invention, and those skilled in the art may make some improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A method for constructing a starting performance model of a marine gas turbine engine, comprising: Step S1: acquiring measurement parameters of the starting performance of a gas turbine engine, analyzing the inlet total temperature and outlet total temperature, and the inlet total pressure and the outlet total pressure of a compressor and a power turbine, and generating low rotation speed characteristics of rotating parts in the starting process of the gas turbine engine by a characteristic identification method, wherein the measurement parameters include the inlet total temperature and outlet total temperature, the inlet total pressure and the outlet total pressure, and the fuel flow rate of the compressor and the power turbine, the output power of the power turbine, and the rotation speeds of the rotors of the gas turbine and the power turbine, and the time required for the rotation speed of the rotor of the gas turbine to reach a predetermined value is the starting time, and the rotating parts include the compressor, the gas turbine, and the power turbine; Step S2: creating a component-level starting mathematical model of the gas turbine engine, constructing a power and torque characteristic of a starter based on the conventional design parameters of the starter, and calculating a power consumption of a compressor and an output power of a gas turbine in a starting process of the gas turbine engine, wherein the components include a starter, an air intake system, a compressor, a combustion chamber, a gas turbine, a power turbine, and an exhaust system of the gas turbine engine; Step S3: constructing a heat transfer model and a temperature sensor model of a high-temperature component of the gas turbine engine and evaluating an influence of heat exchange between the high-temperature gas and the high-temperature component on starting performance of the gas turbine engine, the high-temperature component including the combustion chamber, the gas turbine, and the power turbine; Step S4 of constructing an open-loop control law model and a closed-loop control law model in a starting process of the gas turbine engine, wherein the open-loop starting control law includes a relationship between a gas turbine corrected rotation speed and a fuel supply amount and a relationship between the gas turbine corrected rotation speed and a fuel-air ratio, and the closed-loop starting control law includes a relationship between the gas turbine corrected rotation speed and an acceleration of a rotor of the gas turbine; and (S5) simulating performance in a start-up process of the gas turbine engine under various initial atmospheric conditions, wherein the various initial conditions include various atmospheric temperatures, various atmospheric pressures, and various initial wall temperatures.

2. 2. The method for constructing a starting performance model of a marine gas turbine engine according to claim 1, wherein in step S1, when a certain type of marine gas turbine engine is subjected to a sea surface starting test, the acceleration of the gas turbine rotor is calculated from the rotational speed of the gas turbine rotor during the starting process, and then combined with a rotor dynamics equation to estimate the residual power of the gas turbine rotor at various times during the starting process, and then combined with the inlet total temperature and outlet total temperature, inlet total pressure and outlet total pressure of the compressor and power turbine during the starting process to identify the pressure ratios and efficiency operating characteristic curves of the rotating parts corresponding to different corrected rotational speeds.

3. The rotor dynamics equation is:

3. The method for constructing a starting performance model of a marine gas turbine engine according to claim 2.

4. A method for constructing a starting performance model of a marine gas turbine engine as described in claim 3.

5. A method for constructing a starting performance model of a marine gas turbine engine as described in claim 1.

6. In step S5, 2. The method for establishing a starting performance model for a marine gas turbine engine according to claim 1, wherein the performance of the gas turbine engine during the starting process is simulated under three atmospheric conditions, where the atmospheric temperature and atmospheric pressure are -15°C and 100,740 Pa, 0°C and 100,570 Pa, and 15°C and 100,020 Pa, respectively, and the initial wall temperatures of the combustion chamber, the gas turbine, and the power turbine are set to 15°C for cold start and 60°C, 90°C, and 120°C for hot start, respectively.

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