Performance test device for air Brayton cycle power system

Abstract

The invention provides a performance test device for an air Brayton cycle power system. The performance test device comprises a test prototype (100), and the test prototype (100) comprises an air compressor (101) and a turbine (102); the high-altitude and high-cold simulation system comprises an air pressure simulation tank (201), a vacuum pump (202), an isolating valve (203), a refrigerating machine (204) and a cooler (205), the vacuum pump (202) and the isolating valve (203) are respectively connected to the air pressure simulation tank (201) and used for adjusting and maintaining the target pressure in the air pressure simulation tank (201), and an outlet of the air pressure simulation tank (201) is connected to an inlet of the air compressor (101) through the refrigerating machine (204) in sequence through a pipeline and used for providing a low-temperature and low-pressure working medium for the air compressor (101); an outlet of the turbine (102) is connected to an inlet of the air pressure simulation tank (201) through a pipeline via the cooler (205), and the turbine (102) is used for cooling the working medium after acting and enabling the working medium to flow back to the air pressure simulation tank (201). The device can test the performance of a test prototype in special environments such as high altitude and high cold.

Description

Technical Field

[0001] This application mainly relates to the field of power system testing technology, specifically to a performance testing device for an air Brayton cycle power system, which is particularly suitable for simulating special environments such as high altitude and extreme cold to verify the thermodynamic and mechanical properties of the power system. Background Technology

[0002] An air Brayton cycle power system refers to a power device that uses air as the working fluid and converts thermal energy into mechanical or electrical energy based on the Brayton thermodynamic cycle principle. Its ideal working cycle includes four main processes: ① Isentropic compression: Ambient air is compressed by a compressor, increasing its pressure and temperature; ② Isobaric heating: The compressed, high-temperature, high-pressure air absorbs heat in a heating device (such as a combustion chamber, nuclear reactor heat exchanger, or industrial waste heat recovery unit), further increasing its temperature; ③ Isentropic expansion: The high-temperature, high-pressure air expands in a turbine, doing work, driving the turbine to rotate and output power, while its pressure and temperature decrease; ④ Isobaric cooling: The expanded air releases heat to the environment, completing the cycle. In actual open-loop systems, the working fluid air is directly taken from the environment and returned to the environment after doing work, resulting in a relatively simple and compact system structure.

[0003] Due to its relatively simple structure, high power density, and superior potential efficiency, the air-breathing Brayton cycle propulsion system shows broad application prospects in fields such as small modular nuclear reactors, industrial waste heat recovery, and future nuclear-powered aircraft or deep space exploration energy systems. In practical applications, this type of system often needs to be deployed or operated in special geographical environments such as plateaus and polar regions, or face harsh combined conditions of low air pressure and extreme low temperatures during high-altitude, high-speed flight. Therefore, its thermodynamic performance and long-term mechanical reliability under simulated high-altitude (low-pressure) and frigid (low-temperature) environments must be fully considered and verified during the design phase.

[0004] For open-air Brayton cycle systems, the thin air and reduced pressure at high altitudes directly affect the compressor's inlet flow rate, pressure ratio, and surge boundary, thereby altering the system's operating matching point and efficiency. Simultaneously, the extremely low inlet temperature in frigid environments, while potentially improving theoretical cycle efficiency to some extent, introduces a series of severe challenges: firstly, low-temperature, humid air easily freezes at the compressor inlet or on the blade surface, leading to flow channel blockage, a sharp drop in performance, and even mechanical damage; secondly, pressure-bearing, temperature-bearing, and high-speed rotating metal components in the system (such as compressor and turbine blades, rotors, and casings) may experience decreased material toughness and increased brittleness under sustained low temperatures, thus affecting their fatigue life and safety margin.

[0005] Currently, the known test environments for the thermodynamic performance of open Brayton cycle systems are typically standard ground conditions (normal pressure and temperature). When verifying the system's performance under special environments, an indirect calculation method is commonly used: the prototype is tested under standard test conditions to obtain its performance curves and data, and then, mainly based on similarity principles and gas dynamics formulas, theoretical calculations are performed to convert boundary conditions such as inlet pressure and temperature, in order to deduce the expected performance parameters of the system in the target high-altitude and frigid environment.

[0006] However, this indirect verification method based on data conversion has fundamental flaws and cannot meet the needs of precise research and development. First, this method heavily relies on idealized theoretical models and formula assumptions, failing to realistically reproduce complex and coupled physical processes. For example, it struggles to accurately simulate the subtle changes in unsteady flow inside a compressor under the combined effects of low pressure and low temperature, the heat and mass exchange and aerodynamic shape changes brought about by actual icing processes, and the evolution of the microscopic mechanical properties of materials under sustained low temperatures and alternating stress. Second, this method completely fails to examine and verify the operational behavior of system mechanical components in real, special environments, such as the lubrication characteristics of bearings at low temperatures, performance changes in seals, and thermal stress and deformation of structural components due to excessive temperature differences. Therefore, the accuracy and reliability of data obtained through simple conversion are questionable and cannot serve as a direct criterion for determining whether a system meets performance standards and operates safely and reliably under special environments.

[0007] In summary, the field lacks a testing device capable of physically and accurately simulating the combined environments of high altitude, low air pressure, and extreme cold. The inadequacy of existing technologies results in significant gaps and uncertainties in verifying the core performance and reliability of air Brayton cycle propulsion systems for applications in special environments, severely hindering the design optimization and engineering application of such advanced propulsion systems in related cutting-edge fields. Therefore, there is an urgent need for an innovative testing platform capable of directly conducting comprehensive and empirical thermodynamic performance tests and mechanical performance assessments of prototypes under actual simulated special environmental conditions. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a performance testing device for an air Brayton cycle power system. This device can accurately and reliably simulate special environments such as high altitude and extreme cold, thereby achieving accurate verification of the thermodynamic and mechanical properties of the test prototype.

[0009] To address the aforementioned technical problems, this application provides a performance testing device for an air Brayton cycle power system, comprising: a test prototype including a compressor and a turbine, wherein the outlet of the compressor is connected to the inlet of the turbine via a heating pipe; a high-altitude, high-cold simulation system including a pressure simulation tank, a vacuum pump, an isolation valve, a refrigerator, a cooler, a working fluid output pipe, and a working fluid return pipe; wherein the vacuum pump and the isolation valve are respectively connected to the pressure simulation tank for coordinating and maintaining the target pressure within the pressure simulation tank; the outlet of the pressure simulation tank is connected to the inlet of the compressor via the working fluid output pipe for providing the compressor with a working fluid at a predetermined temperature and pressure, and the refrigerator is located on the working fluid output pipe; the outlet of the turbine is connected to the inlet of the pressure simulation tank via the working fluid return pipe for cooling the working fluid after work and returning it to the pressure simulation tank, and the cooler is located on the working fluid return pipe.

[0010] Optionally, the vacuum pump is connected to the pressure simulation tank and is used to extract the working medium in the pressure simulation tank to reduce its internal pressure; the isolation valve is installed on the pipeline between the pressure simulation tank and the external working medium source and is used to control the external working medium source to replenish the working medium in the pressure simulation tank to increase its internal pressure.

[0011] Optionally, it further includes: a first pressure transmitter for monitoring the working fluid pressure inside the pressure simulation tank; a second thermocouple for monitoring the working fluid temperature after the refrigerator; a control system configured to control the opening and closing of the vacuum pump and the isolation valve based on the monitoring data of the first pressure transmitter, so as to maintain the pressure inside the pressure simulation tank at a preset target high-altitude pressure value; and to control the operating power of the refrigerator based on the monitoring data of the second thermocouple, so as to maintain the working fluid temperature entering the compressor at a preset target high-altitude temperature value.

[0012] Optionally, it also includes: an intake resistance simulation valve, which is disposed on the working fluid output pipeline between the refrigerator and the compressor inlet, for simulating the flow resistance at the compressor inlet.

[0013] Optionally, it further includes: a differential pressure transmitter for monitoring the working fluid pressure drop at the inlet and outlet sides of the intake resistance simulation valve; and a control system configured to adjust the opening of the intake resistance simulation valve based on the monitoring data from the differential pressure transmitter, so as to maintain the pressure difference between the inlet and outlet sides of the intake resistance simulation valve at a preset target resistance value.

[0014] Optionally, it also includes: a second pressure transmitter for monitoring the working fluid pressure on the outlet side of the intake resistance simulation valve.

[0015] Optionally, it further includes: a first thermocouple for monitoring the temperature of the working fluid inside the pressure simulation tank; and a control system configured to control the cooling intensity of the cooler based on the monitoring data of the first thermocouple, so as to reduce the temperature of the working fluid discharged from the turbine to the required temperature inside the pressure simulation tank.

[0016] Optionally, it also includes: a third thermocouple for monitoring the working fluid temperature at the inlet of the cooler; and a fourth thermocouple for monitoring the working fluid temperature at the outlet of the cooler.

[0017] Optionally, it also includes a humidity regulating unit, which is disposed inside the pressure simulation tank or on the working fluid output pipeline at the inlet of the compressor, for regulating the humidity of the working fluid.

[0018] Optionally, the prototype also includes an integrated heuristic unit, which is coaxially connected to the compressor and the turbine.

[0019] Compared with the prior art, this application has the following advantages: 1. This application creatively integrates a low-pressure simulation unit (pressure simulation tank, vacuum pump, isolation valve) with a low-temperature simulation unit (refrigeration unit, cooler) into a coherent test loop through a highly integrated system design. This design not only enables independent and precise control of pressure and temperature parameters, but more importantly, it achieves steady-state and dynamic coupling simulation of low-pressure and low-temperature environments, physically reproducing the core characteristics of "thin and cold" air in high-altitude and frigid regions. This directly overcomes the industry pain point of existing technologies being unable to realistically reproduce special environments, leading to unreliable verification results, and provides a preferred empirical test platform for environmental adaptability research of related products.

[0020] 2. This application features a specially designed intake resistance simulation valve, coupled with high-precision differential pressure monitoring. This allows the experiment to actively set and precisely control the flow resistance at the compressor inlet, thus realistically replicating the intake conditions faced by the prototype in actual engineering applications within the laboratory. This innovative detail elevates performance testing from a simple "ideal characteristic test" to a more engineering-significant "performance assessment under real boundary conditions." The resulting performance data (such as flow-pressure ratio curves and efficiency points) has higher reference value and accuracy for system integration design and performance prediction.

[0021] 3. This application transcends the rudimentary stage of relying on manual experience for parameter adjustment, establishing a fully automated, digital closed-loop control system based on real-time sensor feedback. This system achieves independent closed-loop control of the three most critical environmental and boundary parameters: pressure, temperature, and resistance. It can quickly respond to system disturbances and stabilize each parameter within an extremely narrow set tolerance range. This control method completely eliminates human error and operating condition drift, making multiple experiments conducted at different times and by different operators highly comparable and repeatable, providing a stable and reliable data foundation for scientific research. Simultaneously, automated control greatly simplifies the operation process and improves experimental efficiency.

[0022] 4. This device is not a single-function test bench, but a complete, fully functional, safe, and reliable integrated performance verification platform. It encompasses all aspects from environmental simulation and energy input (simulated heat source) to the prototype under test and comprehensive data acquisition. Its simulated environment is realistic and reliable, with rich and accurate data dimensions, enabling simultaneous evaluation of the system's thermodynamic performance (such as efficiency and power) and observation of its mechanical behavior under extreme conditions (such as vibration and potential icing). Therefore, this device can directly serve the design verification, optimization iteration, reliability assessment, and final product finalization testing of air Brayton cycle systems in fields such as small nuclear reactor power supplies, advanced aerospace propulsion, and industrial waste heat power generation. It provides an indispensable and powerful core R&D tool and technical support for the rapid and healthy development of these cutting-edge technologies, possessing significant engineering application value. Attached Figure Description

[0023] The accompanying drawings are included to provide a further understanding of this application. They are incorporated into and constitute a part of this application. The drawings illustrate embodiments of this application and, together with this specification, serve to explain the principles of this application.

[0024] Figure 1 This is a schematic diagram of a performance testing apparatus for an air Brayton cycle power system according to an embodiment of this application.

[0025] 100 prototypes

[0026] 101 Compressor

[0027] 102 turbine

[0028] 103 Heuristic All-in-One PC

[0029] 104 Power Analyzer

[0030] 201 Pressure Simulation Tank

[0031] 202 Vacuum Pump

[0032] 203 Isolation Valve

[0033] 204 Refrigeration unit

[0034] 205 Cooler

[0035] 206 Intake Resistance Simulation Valve

[0036] 300 heating pipes

[0037] P01 First Pressure Transmitter

[0038] T01 First Thermocouple

[0039] DP11 Differential Pressure Transmitter

[0040] P11 Second Pressure Transmitter

[0041] P12 Third Pressure Transmitter

[0042] T11 Second Thermocouple

[0043] P21 Fourth Pressure Transmitter

[0044] T21 Fifth Thermocouple

[0045] T22 Sixth Thermocouple

[0046] T31 Third Thermocouple

[0047] T32 Fourth Thermocouple

[0048] F21 Flow Meter Detailed Implementation

[0049] 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 should fall within the scope of protection of this application.

[0050] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. In addition, although the terminology used in this application is selected from commonly known and used terms, some terms mentioned in this application's specification may have been chosen by the applicant according to his or her judgment, and their detailed meanings are explained in the relevant sections of this description. Moreover, this application should be understood not only through the actual terms used, but also through the meaning implied by each term.

[0051] like Figure 1 As shown in the figure, the performance testing device for an air Brayton cycle power system provided in this embodiment of the invention mainly includes a test prototype 100 and a high-altitude and cold-weather simulation system.

[0052] The prototype 100 is an air Brayton cycle power system. An air Brayton cycle power system is a heat engine system that uses air as the circulating working fluid, follows the thermodynamic principles of the Brayton cycle, and continuously converts thermal energy into mechanical or electrical energy through the processes of air compression, heating, and expansion. This application does not aim to improve the power system itself, but rather to create a test device that accurately simulates its real-world working environment (high altitude, extreme cold) to verify the system's performance under extreme conditions.

[0053] The prototype 100 is the test object, and its core components include a compressor 101 and a turbine 102. The outlet of the compressor 101 is connected to the inlet of the turbine 102 via a heating pipe 300. In this embodiment, the heating pipe 300 is a simulated reactor device. The simulated reactor device is used to simulate heat sources such as fission heat or industrial waste heat from a nuclear reactor. Its inlet is connected to the outlet of the compressor 101, and its outlet is connected to the inlet of the turbine 102.

[0054] The high-altitude and cold-weather simulation system is coupled with the test prototype 100 to provide simulated high-altitude low-pressure and cold-weather environments for the inlet of compressor 101 and the outlet of turbine 102.

[0055] The high-altitude and cold-weather simulation system includes a pressure simulation tank 201, a vacuum pump 202, an isolation valve 203, a refrigerator 204, a cooler 205, a working fluid output pipeline, and a working fluid return pipeline.

[0056] The pressure simulation tank 201 is used to store a certain capacity of working fluid. The pressure parameters of the working fluid are regulated by a vacuum pump 202 and an isolation valve 203. The vacuum pump 202 is connected to the pressure simulation tank 201 and is used to extract the working fluid in the pressure simulation tank 201 to reduce its internal pressure. The isolation valve 203 is installed on the pipeline between the pressure simulation tank 201 and an external working fluid source and is used to control the external working fluid source to replenish the working fluid into the pressure simulation tank 201 to increase its internal pressure.

[0057] When the pressure inside the pressure simulation tank 201 is lower than the required parameter, the isolation valve 203 is opened, allowing outside air to enter the pressure simulation tank 201 until the pressure inside the tank reaches the required parameter; when the pressure inside the pressure simulation tank 201 is higher than the required parameter, the vacuum pump 202 is turned on until the pressure inside the tank reaches the required parameter. In this way, atmospheric pressure from sea level to altitudes of several thousand meters can be simulated.

[0058] The refrigeration unit 204 is installed on the working fluid output pipeline after the outlet of the pressure simulation tank 201. It is used to deeply cool the working fluid flowing to the compressor 101 to simulate the intake conditions of high cold or extreme low temperature in winter.

[0059] Existing Brayton cycle testing devices typically only perform tests under normal conditions, inferring performance in special environments through data conversion, but they cannot truly reproduce the synergistic effects of low pressure and low temperature. This application, for the first time, integrates a pressure simulation tank, vacuum pump, isolation valve, refrigeration unit, and cooler into a single system, achieving simultaneous simulation of high-altitude (low pressure) and frigid (low temperature) environments. This overall architecture is not a simple combination of existing technologies, but a novel design addressing the pain points of Brayton cycle systems in special environments (such as compressor icing and material embrittlement).

[0060] This application addresses the problem that existing technologies cannot accurately verify performance under special environments, providing more realistic test conditions and avoiding errors caused by data conversion. For example, by simulating low pressure and low temperature, the icing behavior of the compressor and the embrittlement trend of materials can be directly observed, thereby optimizing the system design.

[0061] Cooler 205 is used to reduce the high-temperature gas emitted by turbine 102 to the required temperature inside pressure simulation tank 201. Cooler 205 can reduce the temperature difference between the working fluid inside pressure simulation tank 201 and the inlet of compressor 101, thereby reducing the load on refrigerator 204.

[0062] In existing experimental setups, high-temperature exhaust gas from turbines is typically discharged directly or simply cooled. However, this invention incorporates a cooler at the turbine outlet to cool the high-temperature gas before returning it to the pressure simulation tank. This reduces the temperature difference between the pressure simulation tank and the compressor inlet, thereby lowering the load on the refrigeration unit. This thermal management design improves system energy efficiency, reduces refrigeration unit energy consumption, and makes the experimental setup more energy-efficient and economical.

[0063] Optionally, a third thermocouple T31 and a fourth thermocouple T32 are also included. The third thermocouple T31 is used to monitor the working fluid temperature at the inlet of the cooler 205; the fourth thermocouple T32 is used to monitor the working fluid temperature at the outlet of the cooler 205. This application ensures the stability of the cooling process by monitoring the temperature through the third thermocouple T31 and the fourth thermocouple T32.

[0064] Optionally, the device further includes a first pressure transmitter P01 and a control system (not shown). The first pressure transmitter P01 is used to monitor the working fluid pressure inside the pressure simulation tank 201. The control system is configured to control the opening and closing of the vacuum pump 202 and the isolation valve 203 based on the monitoring data from the first pressure transmitter P01, so as to maintain the pressure inside the pressure simulation tank 201 at a preset target high-altitude pressure value.

[0065] In existing technologies, experimental setups typically maintain atmospheric pressure or simple pressure reduction, failing to dynamically and precisely control the pressure. This invention employs the coordinated regulation of a vacuum pump (for evacuation and pressure reduction) and an isolation valve (for replenishment and pressure increase), combined with real-time monitoring by a first pressure transmitter P01, to achieve precise control and rapid stabilization of the pressure inside the gas pressure simulation tank. This bidirectional regulation mechanism is not readily apparent because it requires addressing the impact of pressure fluctuations on the stability of the Brayton cycle.

[0066] This application can simulate air pressure changes at different high altitudes (such as the air pressure range from 0 meters to 5000 meters), improving the flexibility and accuracy of the experiment. At the same time, this mechanism reduces the risk of pressure overshoot or undershoot, ensuring that the prototype operates under real air pressure conditions.

[0067] Optionally, the device also includes a second thermocouple T11. The second thermocouple T11 is used to monitor the temperature of the working fluid after the refrigerator 204. The control system is also configured to control the operating power of the refrigerator 204 based on the monitoring data of the second thermocouple T11, so as to maintain the temperature of the working fluid entering the compressor 101 at a preset target high-altitude temperature value.

[0068] In a Brayton cycle system, compressor inlet resistance affects intake flow and system efficiency, but existing experimental setups often overlook this. This application specifically includes an intake resistance simulation valve 206. The intake resistance simulation valve 206 is installed on the working fluid output pipeline between the refrigerator 204 and the compressor 101 inlet to simulate the flow resistance at the compressor 101 inlet.

[0069] Optionally, the device further includes a differential pressure transmitter DP11 and a second pressure transmitter P11. The differential pressure transmitter DP11 is used to monitor the working fluid pressure drop on the inlet and outlet sides of the inlet resistance simulation valve 206. The second pressure transmitter P11 is used to monitor the working fluid pressure on the outlet side of the inlet resistance simulation valve 206. The control system is also configured to adjust the opening of the inlet resistance simulation valve 206 based on the monitoring data from the differential pressure transmitter DP11, so as to maintain the pressure difference between the inlet and outlet sides of the inlet resistance simulation valve 206 at a preset target resistance value. This application simulates the inlet resistance (such as pipeline loss, filter resistance) in actual high-altitude environments by adjusting the valve opening, and monitors it in conjunction with the differential pressure transmitter DP11 and the second pressure transmitter P11. This targeted resistance simulation design is not disclosed in the prior art.

[0070] This application more realistically reproduces the operating conditions of the compressor under special environments, avoiding performance evaluation deviations caused by resistance mismatch. For example, in high-altitude areas, thin air may cause changes in resistance, and the intake resistance simulation valve can accurately simulate this effect.

[0071] Optionally, the apparatus also includes a humidity control unit. The humidity control unit is located inside the pressure simulation tank 201 or on the working fluid output pipeline at the inlet of the compressor 101, and is used to regulate the humidity of the circulating working fluid. Adding a humidity control device (such as a humidifier / dehumidifier) ​​to the pressure simulation tank or air intake path simulates the changes in air humidity at high altitudes. This can more realistically reproduce phenomena such as icing and corrosion, improving the accuracy of the experiment.

[0072] Optionally, the heating pipe 300 is a simulated reactor device. The simulated reactor device consists of an electric heater and is used to simulate the fission heat of a nuclear reactor and industrial waste heat. The flow rate of the simulated reactor device is monitored by a flow meter F21, the pressure before the simulated reactor is monitored by a fourth pressure transmitter P21, the temperature before the simulated reactor is monitored by a fifth thermocouple T21, and the temperature after the simulated reactor is monitored by a sixth thermocouple T22.

[0073] In existing technologies, heat source simulation may use simple heaters, but this invention uses an electric heater to simulate nuclear reactor fission heat or industrial waste heat, and integrates it tightly with the test prototype (compressor, turbine, etc.), with comprehensive monitoring via flow meter F21, fourth pressure transmitter P21, fifth thermocouple T21, and sixth thermocouple T22. This integration method ensures the controllability and realism of the heat input parameters, simulating the thermal conditions in actual applications.

[0074] Optionally, the prototype 100 also includes an integrated starter unit 103. The integrated starter unit 103 is coaxially connected to the compressor 101 and the turbine 102. During system startup, it drives the compressor 101 as an electric motor, and after the system is running stably, it generates electricity as a generator, the power of which is monitored by a power analyzer 104.

[0075] Optionally, the device also includes a third pressure transmitter P12. The third pressure transmitter P12 is used to monitor the working fluid pressure after the refrigeration unit 204.

[0076] The working process of the device in this application is as follows: Step 1: Experiment Initialization and Environmental Parameter Setting The operator inputs the target environmental parameters for this experiment into the control system via a human-machine interface. These parameters include at least: the target air pressure value corresponding to the simulated altitude (represented by the absolute pressure inside the air pressure simulation tank 201), and the target inlet air temperature value corresponding to the simulated high-altitude and cold environment (represented by the working fluid temperature at the inlet of compressor 101). In addition, a target inlet air resistance value (represented by the pressure difference before and after inlet air resistance simulation valve 206) can be set according to the experiment design. The control system stores these target values ​​as the core setpoints for closed-loop control.

[0077] Step 2: Establishment and stabilization of a high-altitude, low-pressure environment

[0078] The control system reads the actual pressure value inside the pressure simulation tank 201, which is monitored in real time by the first pressure transmitter P01, and compares it with the set target pressure value. Based on the comparison result, the system performs dynamic adjustment: If the actual pressure is higher than the target value, the control system starts the vacuum pump 202 to pump air, while closing or keeping the isolation valve 203 closed to reduce the pressure inside the tank.

[0079] If the actual pressure is lower than the target value, the control system shuts down the vacuum pump 202 and precisely adjusts the opening of the isolation valve 203 to allow ambient air to slowly flow into the tank under the action of pressure difference, thereby increasing the pressure.

[0080] This adjustment process uses a closed-loop control algorithm (such as PID control) to continuously feed back and fine-tune the pressure in the pressure simulation tank 201, which quickly converges and stabilizes at the target pressure value, thereby accurately simulating the required high-altitude, low-pressure environment.

[0081] Step 3: Establishment and stabilization of high-altitude and low-temperature environments

[0082] Simultaneously or subsequently, the control system compares the working fluid temperature at the outlet of the refrigerator 204 (i.e., before the inlet of the compressor 101), which is fed back in real time by the second thermocouple T11, with the set target inlet air temperature. The control system dynamically adjusts the cooling power of the refrigerator 204 (e.g., adjusting the compressor frequency, refrigerant flow rate, etc.): if the actual temperature is higher than the target value, the cooling power is increased; if the actual temperature is lower than the target value, the cooling power is decreased.

[0083] This closed-loop temperature control ensures that the temperature of the working fluid entering the compressor 101 of the test prototype is precisely controlled at the target low temperature value, thereby stably simulating a cold environment.

[0084] Step 4: Simulation of intake resistance conditions

[0085] To more realistically reproduce the inlet conditions of the prototype during actual installation, the control system compares the working fluid pressure drop across the inlet resistance simulation valve 206, monitored by the differential pressure transmitter DP11, with a preset target resistance value. The system dynamically and precisely adjusts the valve opening by driving the valve actuator, thereby changing its flow resistance and ensuring the measured differential pressure accurately matches the preset value. This step provides more realistic boundary conditions for performance testing.

[0086] Step 5: Trial Operation and Comprehensive Data Acquisition

[0087] Once all the above environmental parameters (pressure, temperature, resistance) have reached and remained stable, the control system issues a command to start the test prototype 100.

[0088] After the prototype is started, the heating pipe 300 begins to operate, heating the high-pressure working fluid from the compressor 101 to simulate a real heat source input. The high-temperature, high-pressure working fluid enters the turbine 102, expands, and performs work, driving the turbine rotor to rotate. The mechanical work output by the turbine 102 drives the coaxially connected heuristic unit 103. During the start-up phase, the heuristic unit 103 can act as an auxiliary drive for the electric motor; during the stable operation phase, it acts as a generator, outputting electrical power, the electrical parameters of which are precisely measured by the power analyzer 104. The working fluid discharged from the turbine 102 flows through the cooler 205 to be cooled before returning to the pressure simulation tank 201, completing one complete test cycle.

[0089] Throughout the entire test run (including startup, steady-state operation, and variable operating conditions), a network of measuring instruments distributed across key nodes of the device (such as pressure transmitters P01, P11, P12, P21; thermocouples T01, T11, T21, T22, T31, T32; differential pressure transmitter DP11; flow meter F21; power analyzer 104, etc.) synchronously, in real-time, and at high frequency acquires data. The control system records and stores this massive amount of time-series data. Based on this data, the thermodynamic performance indicators of the prototype under simulated special environments (such as compressor pressure ratio and efficiency, turbine expansion ratio and efficiency, system cycle efficiency, power generation, etc.) and mechanical state parameters (which can be monitored through additional vibration and strain sensors) can be comprehensively calculated and evaluated, thereby completing the accurate verification and evaluation of its performance under extreme environments. The entire process achieves a high degree of automation and integration in environmental simulation and performance testing.

[0090] The performance testing apparatus for an air Brayton cycle power system described in this application constructs a closed-loop thermodynamic test circuit with precisely controllable boundary conditions. The core design concept of this circuit is to simulate a "controlled open-loop" environment. Physically, the working fluid (air) forms a closed-loop flow within the apparatus, allowing for precise measurement and repeatable testing. Thermodynamically, the source state of the working fluid (pressure simulation tank) is precisely controlled through the high-altitude, high-cold simulation system, effectively providing the test prototype with a working fluid source possessing the same pressure, temperature, and composition as a real high-altitude, high-cold environment. This physically replicates the actual air intake conditions of an open Brayton cycle in a special environment within a laboratory setting. This design cleverly combines the testing requirements of an open-loop system with the controllability and measurability of a closed-loop test system, forming the cornerstone of this apparatus's accurate environmental simulation.

[0091] The intake resistance simulation valve is a key component for improving the realism of the test. Its function is to simulate various flow resistances at the compressor inlet in actual applications, including but not limited to: intake filters, anti-icing grilles, silencers, inlet pipe bends, and total pressure loss caused by boundary layers. This valve is preferably a regulating valve with linear or equal percentage flow characteristics, and its opening degree has a definite correspondence with the flow resistance coefficient, which can be obtained through prior calibration. The differential pressure transmitter DP11 monitors the pressure difference across the valve in real time, which directly reflects the magnitude of the simulated resistance. The control system, based on a preset target resistance curve (which can be a fixed value or a function of flow rate), adjusts the valve opening to make the measured pressure difference track the target value, thereby dynamically and accurately reproducing complex and variable inlet resistance conditions.

[0092] The control system is the core component ensuring the automatic, precise, and safe operation of the testing equipment. Its software platform typically includes, but is not limited to, the following functional modules: user management and human-machine interaction module, test procedure editing and execution module, real-time data acquisition and monitoring module, historical data storage and playback module, alarm management and safety interlock module, and automatic report generation module. The control algorithm, based on basic PID control, can further incorporate advanced strategies such as feedforward compensation and fuzzy inference to improve the regulation quality for controlled objects with large inertia and nonlinear characteristics (such as the temperature and pressure of large pressure simulation tanks). All control logic has undergone thorough simulation and testing to ensure its robustness.

[0093] This application achieves fully automatic, high-precision real-time control of key physical parameters such as pressure, temperature, and resistance in the test environment through a highly integrated and responsive closed-loop control system, fundamentally ensuring the long-term stability of test conditions and strict repeatability between multiple tests. This closed-loop control system operates on a "sensing-decision-execution" framework. Specifically, the sensing layer consists of a high-precision, fast-response sensor network, including but not limited to the first pressure transmitter P01, the second thermocouple T11, and the differential pressure transmitter DP11. These sensors act as the system's "sensors," continuously and in real-time acquiring raw signals such as the absolute pressure inside the pressure simulation tank, the compressor inlet temperature, and the pressure difference across the inlet resistance simulation valve, converting them into standard electrical signals and transmitting them to the central controller. The decision-making layer is typically centered on a programmable logic controller (PLC) or an industrial control computer (IPC). Advanced control algorithms (such as fuzzy PID control and adaptive control) are pre-embedded within the controller. The algorithm performs high-speed comparison and calculation between real-time measurements from sensors and user-preset target values ​​(such as target pressure, target low temperature, and target flow resistance at a certain altitude), generating precise control commands in real time. For example, the algorithm not only calculates the deviation between the current pressure and the target pressure, but also predicts future conditions based on the trend of the deviation, thereby making adjustment decisions in advance. The execution layer consists of a series of controlled electromechanical devices, including the vacuum pump 202, isolation valve 203, refrigerator 204, and inlet resistance simulation valve 206. They act as the "hands and feet" of the system, strictly and rapidly executing the commands issued by the controller. For example, the controller precisely controls the pressure inside the pressure simulation tank by adjusting the start / stop and frequency of the vacuum pump and the opening degree of the isolation valve; it precisely controls the temperature of the outlet working fluid by adjusting the power of the refrigerator compressor or the refrigerant flow rate; and it precisely sets the flow resistance by driving the motor of the inlet resistance simulation valve to change the valve core position.

[0094] The advantage of this closed-loop control lies in the dynamic adjustment process. When a parameter deviates from the setpoint due to changes in the operating conditions of the test prototype or external disturbances, the sensor immediately detects this minute deviation. The controller calculates a correction scheme within milliseconds and drives the actuator to move, enabling the parameter to quickly and smoothly return to the setpoint, effectively suppressing fluctuations. For example, when a sudden increase in turbine power leads to an increase in exhaust temperature, which may affect the temperature balance inside the pressure simulation tank, the control system can enhance the efficiency of the cooler 205 in advance or synchronously, and compensate through the refrigerator 204, thereby controlling the change in compressor inlet temperature within a very small tolerance range.

[0095] Therefore, this closed-loop control system ensures that the core environmental parameters (pressure, temperature, and resistance) are strictly locked at preset values, whether it is a steady-state performance test lasting for several hours or a comparative test that needs to be repeated multiple times. This precision and stability, which surpasses manual adjustment, is the fundamental guarantee for obtaining reliable, comparable, and high-quality test data, and is also one of the core advancements of this invention compared to traditional test devices that rely on manual operation or open-loop control.

[0096] In summary, this application aims to overcome the limitations of existing technologies and provide an integrated, high-fidelity environmental simulation and performance testing platform. This device can not only physically reproduce single specific environmental parameters, but also accurately simulate the complex composite environment of high altitude, low air pressure, and extreme cold, thus filling the long-standing gap in the field of real-world environmental empirical testing capabilities. By constructing a test loop with fully controllable boundary conditions and complete measurement parameters, this application enables researchers to conduct in-depth, systematic, and safe evaluations of the comprehensive performance of air Brayton cycle power systems under extreme conditions in laboratory settings. This significantly accelerates the research and development iteration and reliability verification process of related technologies, possessing significant engineering practical value and broad industry application prospects.

[0097] Those skilled in the art will understand that the specific selection of each component in the apparatus can be optimized based on actual experimental needs, budget, and performance indicators. For example, the vacuum pump can be a rotary vane, Roots, or dry screw vacuum pump; the refrigeration unit can be a single-stage compression, cascade, or pre-cooling refrigeration cycle system, depending on the required minimum temperature; the various valves (such as isolation valves and inlet resistance simulation valves) can be electrically, pneumatically, or hydraulically driven, and matched with corresponding flow characteristics and diameters. The accuracy class, range, and response time of the measuring instruments (pressure transmitters, thermocouples, flow meters, etc.) should meet the accuracy and dynamic characteristics requirements of the experimental data acquisition, typically requiring an accuracy of 0.5 or better. These conventional selection and adaptation tasks are all within the knowledge and capabilities of those skilled in the art.

[0098] The application of the test apparatus described in this application is not limited to performance evaluation of complete prototypes. Through partial modifications or the addition of specialized fixtures, this platform is also suitable for conducting individual environmental adaptability tests on key components of the Brayton cycle system (such as compressor impellers, turbine nozzle rings, and regenerators). Furthermore, by adjusting the heat source type and power regulation method of the simulated reactor device, the apparatus can be easily connected to and simulate different primary energy sources, such as nuclear, solar, and chemical energy, thereby expanding into a general-purpose special environment test platform for various advanced power cycles. This excellent scalability allows the technical value of this application to be realized in a wider range of research fields.

[0099] To ensure the scientific rigor, repeatability, and comparability of test results, any formal performance test conducted using this device must adhere to a pre-established and rigorous test outline. This outline clearly defines the test objectives, test conditions (set values ​​and tolerances of environmental parameters), test procedures, list of data to be collected, sensor calibration status, and data post-processing methods. Before each test, key measuring instruments must undergo online zero-point calibration or offline traceability to eliminate system errors. During the test, the control system will automatically record the time-series data of all parameters, and the data storage format facilitates importing into professional analysis software for processing. Through the above standardized and procedural test methods, the accuracy and reliability of the final performance evaluation conclusions are fundamentally guaranteed.

[0100] Given that the testing process involves vacuum, cryogenics, potentially high temperatures, and electrical equipment, the design and operation of this device must strictly adhere to all safety regulations. In addition to the soft safety interlocks in the control software, necessary safety protection facilities should be implemented at the hardware level, such as: mechanical safety relief valves on the pressure simulation tank, refrigerant leak detection and alarm devices, thermal insulation and warning signs for high-temperature pipelines and equipment, overload and short-circuit protection for the electrical system, and emergency stop buttons. Operators must undergo specialized training and be familiar with the emergency response plan. All these measures together constitute multiple lines of defense to ensure the safety of testing personnel and equipment.

[0101] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0102] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0103] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0104] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0105] Some aspects of this application can be executed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The aforementioned hardware or software may be referred to as a "data block," "module," "engine," "unit," "component," or "system." The processor may be one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. Furthermore, aspects of this application may manifest as computer products residing in one or more computer-readable media, including computer-readable program code. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, magnetic tapes, etc.), optical discs (e.g., compressed CDs, digital multifunction DVDs, etc.), smart cards, and flash memory devices (e.g., cards, sticks, key drives, etc.).

[0106] A computer-readable medium may contain a propagated data signal containing computer program code, for example, on baseband or as part of a carrier wave. This propagated signal may take various forms, including electromagnetic, optical, and so on, or suitable combinations thereof. A computer-readable medium can be any computer-readable medium other than a computer-readable storage medium, which can be connected to an instruction execution system, apparatus, or device to enable communication, propagation, or transmission of a program for use. The program code located on the computer-readable medium can be propagated through any suitable medium, including radio, cable, fiber optic cable, radio frequency signals, or similar media, or any combination of the above media.

[0107] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0108] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of scope in some embodiments of this application are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

[0109] Although this application has been described with reference to specific embodiments, those skilled in the art should recognize that the above embodiments are only used to illustrate this application, and various equivalent changes or substitutions can be made without departing from the spirit of this application. Therefore, any changes or modifications to the above embodiments within the essential spirit of this application will fall within the scope of the claims of this application.

Claims

1. A performance testing apparatus for an air Brayton cycle power system, characterized in that, include: The prototype (100) includes a compressor (101) and a turbine (102), the outlet of which is connected to the inlet of the turbine (102) via a heating pipe (300); The high-altitude and cold-weather simulation system includes a pressure simulation tank (201), a vacuum pump (202), an isolation valve (203), a refrigerator (204), a cooler (205), a working fluid output pipeline, and a working fluid return pipeline; The vacuum pump (202) and the isolation valve (203) are respectively connected to the pressure simulation tank (201) to coordinately regulate and maintain the target pressure inside the pressure simulation tank (201); The outlet of the pressure simulation tank (201) is connected to the inlet of the compressor (101) through the working fluid output pipeline, which is used to provide the compressor (101) with a working fluid at a predetermined temperature and a predetermined pressure. The refrigerator (204) is located on the working fluid output pipeline. The outlet of the turbine (102) is connected to the inlet of the pressure simulation tank (201) through the working fluid return pipeline, which is used to cool the working fluid after it has done work and return it to the pressure simulation tank (201). The cooler (205) is located on the working fluid return pipeline.

2. The performance testing apparatus as described in claim 1, characterized in that, The vacuum pump (202) is connected to the pressure simulation tank (201) and is used to extract the working fluid in the pressure simulation tank (201) to reduce its internal pressure; The isolation valve (203) is installed on the pipeline between the pressure simulation tank (201) and the external working medium source, and is used to control the external working medium source to replenish the working medium into the pressure simulation tank (201) to increase its internal pressure.

3. The performance testing apparatus as described in claim 1, characterized in that, Also includes: The first pressure transmitter (P01) is used to monitor the working fluid pressure inside the pressure simulation tank (201); The second thermocouple (T11) is used to monitor the temperature of the working fluid after the refrigerator (204); The control system is configured to control the opening and closing of the vacuum pump (202) and the isolation valve (203) based on the monitoring data of the first pressure transmitter (P01) to maintain the pressure in the pressure simulation tank (201) at a preset target high-altitude pressure value; and to control the operating power of the refrigerator (204) based on the monitoring data of the second thermocouple (T11) to maintain the working fluid temperature entering the compressor (101) at a preset target high-altitude temperature value.

4. The performance testing apparatus as described in claim 1, characterized in that, Also includes: An intake resistance simulation valve (206) is installed on the working fluid output pipeline between the refrigerator (204) and the compressor (101) inlet to simulate the flow resistance at the compressor (101) inlet.

5. The performance testing apparatus as described in claim 4, characterized in that, Also includes: Differential pressure transmitter (DP11) is used to monitor the working fluid pressure drop on the inlet and outlet sides of the inlet resistance simulation valve (206); The control system is configured to adjust the opening of the intake resistance simulation valve (206) based on the monitoring data of the differential pressure transmitter (DP11) so as to maintain the pressure difference between the inlet side and the outlet side of the intake resistance simulation valve (206) at a preset target resistance value.

6. The performance testing apparatus as described in claim 4, characterized in that, Also includes: The second pressure transmitter (P11) is used to monitor the working fluid pressure on the outlet side of the intake resistance simulation valve (206).

7. The performance testing apparatus as described in claim 1, characterized in that, Also includes: The first thermocouple (T01) is used to monitor the temperature of the working fluid inside the pressure simulation tank (201); The control system is configured to control the cooling intensity of the cooler (205) based on the monitoring data of the first thermocouple (T01) to reduce the temperature of the working fluid discharged from the turbine (102) to the required temperature inside the pressure simulation tank (201).

8. The performance testing apparatus as described in claim 6, characterized in that, Also includes: The third thermocouple (T31) is used to monitor the working fluid temperature at the inlet of the cooler (205); The fourth thermocouple (T32) is used to monitor the working fluid temperature at the outlet of the cooler (205).

9. The performance testing apparatus as described in claim 1, characterized in that, It also includes a humidity control unit, which is installed inside the pressure simulation tank (201) or on the working fluid output pipeline at the inlet of the compressor (101) to control the humidity of the working fluid.

10. The performance testing apparatus as described in claim 1, characterized in that, The test prototype (100) also includes an integrated heuristic unit (103), which is coaxially connected to the compressor (101) and the turbine (102).

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