Method and system for designing ignition frequency of turboshaft engine based on hot start characteristics

Abstract

The application discloses a kind of based on hot starting characteristic turboshaft engine ignition frequency design method and system, the starting ignition frequency design method is based on the real test data of turboshaft engine to determine the upper and lower limit of reliable ignition speed interval, and the minimum ignition frequency is determined in combination with the hot starting characteristic of turboshaft engine, for starting requirement more strict, the minimum ignition frequency corresponding to different models of turboshaft engine can be accurately designed, can better fit the starting performance and requirement of different models of turboshaft engine, greatly improve the starting success rate of turboshaft engine.

Description

Technical Field

[0001] This invention relates to the field of aero-engine start-up control technology, and in particular to a method and system for designing the ignition frequency of a turboshaft engine based on hot start characteristics, electronic equipment, and a computer-readable storage medium. Background Technology

[0002] The starting process of an aero-engine turboshaft engine involves several key steps: starter motor rotation, ignition by the ignition device, and fuel supply from the fuel system. Due to the engine's characteristics, the reliable ignition speed range during starting is very narrow (this ignition speed refers to the gas generator speed). When the gas generator speed is low, the fuel system pressure has not yet been established, the nozzle atomization effect is poor, and the required Sothel average diameter for ignition cannot be achieved, which can easily lead to start-up failure. Conversely, when the gas generator speed is high, the gas flow velocity at the ignition nozzle cross-section is too fast, which is not conducive to the formation of a stable vortex zone for combustion, and can also easily lead to start-up failure. Furthermore, to ignite within a very short reliable ignition speed range, the selection of the ignition frequency is crucial. If the ignition frequency is too low, the number of sparks generated within that ignition speed range may be insufficient, or even nonexistent, leading to start-up failure. If the ignition frequency is too high, the ignition nozzle may be damaged or fail prematurely, reducing its service life and reliability, and increasing the probability of start-up failure in the later stages. Currently, when developing new turboshaft engines, reliable ignition speed ranges and starting ignition frequencies are usually designed based on human experience or by referring to other turboshaft engine models. However, since the starting performance and requirements of different turboshaft engine models are different, the reliable ignition speed range and ignition frequency selected based on experience or reference may not be completely compatible with the current turboshaft engine, resulting in a certain risk of starting failure and a low starting success rate. Summary of the Invention

[0003] This invention provides a method and system for designing the ignition frequency of a turboshaft engine based on its hot start characteristics, as well as electronic equipment and a computer-readable storage medium. It can accurately design the minimum ignition frequency corresponding to different models of turboshaft engines, better match the starting performance and requirements of different models of turboshaft engines, and greatly improve the starting success rate of turboshaft engines.

[0004] According to one aspect of the present invention, a method for designing the ignition frequency of a turboshaft engine based on hot start characteristics is provided, comprising the following:

[0005] Based on the nozzle atomization test results, the nozzle inlet pressure value that meets the Sotelle average diameter condition is determined, and the lower limit of the reliable ignition speed range is determined based on the nozzle inlet pressure value.

[0006] The upper limit of the reliable ignition speed range is determined based on the test results of the compressor components and the design parameters of the combustion chamber;

[0007] The minimum ignition frequency is determined based on the hot start characteristics and the range of values ​​for the reliable ignition speed range.

[0008] Furthermore, the process of determining the upper limit of the reliable ignition speed range based on compressor component test results and combustion chamber design parameters includes the following:

[0009] Based on the test results of the compressor components, a mapping relationship between the gas generator speed and the compressor inlet air flow rate is constructed;

[0010] The design value of the air flow rate ratio of the right section of the ignition nozzle in the combustion chamber flame tube and the design value of the cross-sectional area of ​​the flame tube at the ignition nozzle installation position are obtained. The corresponding inlet air flow rate value is calculated based on the cross-sectional flow velocity limit condition at the ignition nozzle installation section.

[0011] Substitute this inlet air flow rate value into the mapping relationship between the gas generator speed and the compressor inlet air flow rate to calculate the gas generator speed value that satisfies the cross-sectional velocity limit condition, and use it as the upper limit of the reliable ignition speed range.

[0012] Furthermore, the inlet airflow rate that satisfies the cross-sectional velocity limit is calculated based on the following formula:

[0013] ;

[0014] in, This represents the inlet air flow rate value when the cross-sectional velocity limit condition is met. Indicates air density, This indicates the design value of the cross-sectional area of ​​the flame tube at the installation position of the ignition nozzle. This indicates the design value of the airflow percentage on the right side of the ignition nozzle.

[0015] Furthermore, the process of determining the minimum ignition frequency based on the hot start characteristics and the range of reliable ignition speeds includes the following:

[0016] Based on the test results of immediate restart after shutdown, a mapping relationship between the gas generator speed acceleration and the gas generator speed is constructed.

[0017] Substitute the lower limit of the reliable ignition speed range into the mapping relationship to obtain the corresponding gas generator speed acceleration value, and calculate the shortest passage time of the reliable ignition speed range based on the gas generator speed acceleration value.

[0018] Based on the minimum transit time and spark quantity constraints within the reliable ignition speed range, the minimum ignition frequency of the turboshaft engine is calculated.

[0019] Furthermore, the shortest transit time within the reliable ignition speed range is calculated based on the following formula:

[0020] ;

[0021] Where t represents the shortest transit time within the reliable ignition speed range. This indicates the upper limit of the reliable ignition speed range. This represents the lower limit of the reliable ignition speed range. This represents the gas generator speed acceleration value corresponding to the lower limit of the reliable ignition speed range in the mapping relationship between gas generator speed acceleration and gas generator speed.

[0022] Furthermore, the minimum ignition frequency of the turboshaft engine is calculated based on the following formula:

[0023] ;

[0024] in, The minimum ignition frequency of the turboshaft engine is represented by t, the shortest transit time within the reliable ignition speed range is represented by , and S represents the number of sparks required for successful ignition within the reliable ignition speed range. This represents the gas generator speed acceleration value corresponding to the lower limit of the reliable ignition speed range in the mapping relationship between gas generator speed acceleration and gas generator speed. This indicates the design value of the airflow percentage on the right side of the ignition nozzle. This indicates the design value of the cross-sectional area of ​​the flame tube at the installation position of the ignition nozzle. Indicates air density, This represents the nozzle inlet pressure value when the Sothel mean diameter condition is met. , , , All are constants.

[0025] Furthermore, the process of determining the lower limit of the reliable ignition speed range based on the nozzle inlet pressure value includes the following:

[0026] A whole-machine start-up test was conducted, and the measured values ​​of nozzle inlet pressure and gas generator speed were recorded during the whole-machine test. A mapping relationship between nozzle inlet pressure and gas generator speed was constructed. The nozzle inlet pressure value that meets the Sotelle mean diameter condition was substituted into the mapping relationship to obtain the gas generator speed value that meets the Sotelle mean diameter condition, which was used as the lower limit value of the reliable ignition speed range.

[0027] In addition, the present invention also provides a turboshaft engine ignition frequency design system based on hot start characteristics, comprising:

[0028] The lower limit setting module is used to determine the nozzle inlet pressure value that meets the Sotelle average diameter condition based on the nozzle atomization test results, and to determine the lower limit value of the reliable ignition speed range based on the nozzle inlet pressure value.

[0029] The upper limit setting module is used to determine the upper limit of the reliable ignition speed range based on the test results of the compressor components and the design parameters of the combustion chamber;

[0030] The minimum ignition frequency calculation module is used to determine the minimum ignition frequency based on the range of values ​​for hot start characteristics and reliable ignition speed range.

[0031] In addition, the present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method described above by calling the computer program stored in the memory.

[0032] In addition, the present invention also provides a computer-readable storage medium for storing a computer program for designing the ignition frequency of a turboshaft engine based on hot start characteristics, wherein the computer program executes the steps of the method described above when running on a computer.

[0033] The present invention has the following beneficial effects:

[0034] The present invention provides a design method for the ignition frequency of a turboshaft engine based on its hot start characteristics. This method determines the upper and lower limits of the reliable ignition speed range based on real test data of the turboshaft engine, and determines the minimum ignition frequency by combining the hot start characteristics of the turboshaft engine. This method has stricter starting requirements and can accurately design the minimum ignition frequency corresponding to different models of turboshaft engines. It can better match the starting performance and requirements of different models of turboshaft engines and greatly improve the starting success rate of turboshaft engines.

[0035] In addition, the turboshaft engine ignition frequency design system based on hot start characteristics of the present invention also has the above-mentioned advantages.

[0036] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0037] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0038] Figure 1 This is a flowchart illustrating a preferred embodiment of the ignition frequency design method for a turboshaft engine based on hot start characteristics.

[0039] Figure 2 yes Figure 1 A schematic diagram of the sub-process of step S2;

[0040] Figure 3 yes Figure 1 A schematic diagram of the sub-process of step S3;

[0041] Figure 4 This is a schematic diagram of the module structure of a turboshaft engine ignition frequency design system based on hot start characteristics, according to another embodiment of this application. Detailed Implementation

[0042] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0043] Reference Figure 1 A preferred embodiment of this application provides a method for designing the ignition frequency of a turboshaft engine based on hot start characteristics, including the following:

[0044] Step S1: Determine the nozzle inlet pressure value that meets the Sotelle average diameter condition based on the nozzle atomization test results, and determine the lower limit of the reliable ignition speed range based on the nozzle inlet pressure value.

[0045] Step S2: Determine the upper limit of the reliable ignition speed range based on the test results of the compressor components and the design parameters of the combustion chamber;

[0046] Step S3: Determine the minimum ignition frequency based on the hot start characteristics and the range of values ​​for the reliable ignition speed range.

[0047] It is understood that the ignition frequency design method for turboshaft engines based on hot start characteristics in this embodiment determines the upper and lower limits of the reliable ignition speed range based on real test data of turboshaft engines, and determines the minimum ignition frequency in combination with the hot start characteristics of turboshaft engines. It has stricter starting requirements and can accurately design the minimum ignition frequency corresponding to different models of turboshaft engines. It can better match the starting performance and requirements of different models of turboshaft engines and greatly improve the starting success rate of turboshaft engines.

[0048] In step S1, based on development experience, when the Sotelle Mean Diameter (SMD) of the oil mist meets the Sotelle Mean Diameter condition, the aero-turboshaft engine can successfully ignite. The Sotelle Mean Diameter condition is typically set to be no higher than 80 μm. The Sotelle Mean Diameter of the oil mist is directly proportional to the pre-injection pressure; the higher the pre-injection pressure, the smaller the SMD. Therefore, to obtain the pre-injection pressure value with an SMD of 80 μm, a nozzle atomization test is required. Specifically, a pressure sensor is installed in front of the nozzle to measure the pre-injection pressure. During the nozzle atomization test, a mature SMD measurement method and laser measurement instrument are used, and the SMD is calculated based on the following formula: ,in, The Sothel mean diameter represents the oil mist. Indicates the first i The diameter of the particles, Indicates the first i The number of particles, Indicates the first i The volume of the particles is calculated using the following formula: , Indicates the first i The surface area of ​​particles is calculated using the following formula: After completing the nozzle atomization test, the nozzle inlet pressure values ​​corresponding to different SMD values ​​were obtained. Then, the nozzle inlet pressure value corresponding to an SMD of 80μm was extracted. (That is, the nozzle inlet pressure value when the Sothel average diameter condition is met). Furthermore, nozzle atomization testing is a mature existing testing method; the specific testing process and principles will not be elaborated here.

[0049] In addition, the nozzle inlet pressure value that satisfies the Sothel mean diameter condition is obtained. Then, the lower limit of the reliable ignition speed range is determined based on the nozzle inlet pressure value. The process of determining the lower limit of the reliable ignition speed range based on the nozzle inlet pressure value includes the following:

[0050] A whole-machine start-up test was conducted, and the measured values ​​of nozzle inlet pressure and gas generator speed were recorded during the whole-machine test. A mapping relationship between nozzle inlet pressure and gas generator speed was constructed. The nozzle inlet pressure value that meets the Sotelle mean diameter condition was substituted into the mapping relationship to obtain the gas generator speed value that meets the Sotelle mean diameter condition, which was used as the lower limit value of the reliable ignition speed range.

[0051] Specifically, the nozzle inlet pressure is directly proportional to the gas generator speed. During the start-up test, both the nozzle inlet pressure and the gas generator speed are measured simultaneously. Based on the measurement results, a mapping relationship between the nozzle inlet pressure and the gas generator speed can be fitted, which can be expressed as: Where ng represents the rotational speed of the gas generator. Indicates the pressure before the nozzle. and It is a constant and can be obtained from any two sets of data. The solution is obtained. Then, the nozzle inlet pressure value that satisfies the Sothel average diameter condition extracted earlier is used. Substituting the above mapping relationship, the gas generator speed ng1 that satisfies the Sothel average diameter condition can be calculated, which can be expressed as: The gas generator speed value ng1 is the speed threshold that makes the SMD of fuel nozzle atomization below 80μm. Therefore, this invention uses it as the lower limit of the reliable ignition speed range.

[0052] It is understood that this invention first determines the nozzle inlet pressure value that meets the Sotère mean diameter condition through nozzle atomization tests. When the Sotère mean diameter condition is met, the aero-turboshaft engine can ignite successfully. Then, based on the results of the whole-engine start-up test, the mapping relationship between the nozzle inlet pressure and the gas generator speed is obtained. Substituting the nozzle inlet pressure value that meets the Sotère mean diameter condition into this mapping relationship, the gas generator speed value that meets the Sotère mean diameter condition can be obtained. This is the speed threshold value that makes the fuel nozzle atomized SMD lower than 80μm. Thus, the lower limit value of the reliable ignition speed range can be accurately obtained. The lower limit value is set according to the component test results and whole-engine test results of the turboshaft engine, which can better match the start-up performance and requirements of different models of turboshaft engines, ensuring the accuracy and reliability of the reliable ignition speed range.

[0053] In addition, such as Figure 2 As shown, in step S2, the process of determining the upper limit of the reliable ignition speed range based on the test results of the compressor components and the design parameters of the combustion chamber includes the following:

[0054] Step S21: Based on the test results of the compressor components, construct the mapping relationship between the gas generator speed and the compressor inlet air flow rate;

[0055] Step S22: Obtain the design value of the air flow rate ratio of the right section of the ignition nozzle in the combustion chamber flame tube and the design value of the cross-sectional area of ​​the flame tube at the ignition nozzle installation position. Calculate the corresponding inlet air flow rate value based on the cross-sectional velocity limit condition at the ignition nozzle installation section.

[0056] Step S23: Substitute the inlet air flow rate value into the mapping relationship between the gas generator speed and the compressor inlet air flow rate to calculate the gas generator speed value that meets the cross-sectional flow velocity limit condition, and use it as the upper limit value of the reliable ignition speed range.

[0057] Specifically, since the compressor inlet airflow of a turboshaft engine is directly proportional to the gas generator speed, the higher the gas generator speed, the greater the compressor inlet airflow. By conducting compressor component tests and simultaneously measuring the inlet airflow and gas generator speed during the tests, and then constructing a mapping relationship between the gas generator speed and the compressor inlet airflow based on the measurement results, it can be expressed as: ,in, This indicates the inlet air flow rate of the compressor. and It is a constant, based on any two sets of measurement data. The solution is obtained.

[0058] Then, based on the design results of the combustion chamber, the design value of the airflow ratio of the right section of the ignition nozzle inside the combustion chamber flame tube is obtained. Design value of the cross-sectional area of ​​the flame tube at the ignition nozzle installation location Among them, the airflow ratio of the right section of the ignition nozzle is the design value. This refers to the ratio of the airflow entering the flame tube from the right side of the ignition nozzle to the total airflow in the combustion chamber. It is the design value of the airflow percentage after the combustion chamber design is completed. This is a fixed value; similarly, after the combustion chamber design is completed, the design value of the cross-sectional area of ​​the flame tube at the ignition nozzle installation location is... This is also a fixed value. Based on research and development experience, when the actual flow velocity at the ignition nozzle installation section meets the section flow velocity limit (usually 10 m / s), the combustion chamber can reliably ignite. Once the section flow velocity limit is exceeded, the combustion chamber ignition becomes unstable. Moreover, during the start-up phase, as the gas generator speed increases, the airflow into the combustion chamber not only increases, but the flow velocity at the ignition nozzle installation section also becomes increasingly faster. Therefore, the gas generator speed corresponding to the section flow velocity limit (usually 10 m / s) can be considered the upper limit of the reliable ignition speed range. The design value is based on the airflow ratio. and the inlet air flow of the compressor The airflow at the ignition nozzle mounting section can be calculated as follows: × Combining this with the formula for mass airflow rate, we can see that: , This represents the air density inside the flame tube. Since the pressure ratio is relatively low in the ignition speed range, it can be approximated as the air density of the current environment. This indicates the flow velocity at the installation section of the ignition nozzle. This represents the design cross-sectional area of ​​the flame tube at the ignition nozzle mounting location. =10m / s, and the inlet air flow rate that meets the cross-sectional velocity limit can be calculated using the following formula:

[0059] ;

[0060] in, This represents the inlet air flow rate when the cross-sectional velocity limit is met.

[0061] Finally, Substitute the mapping relationship between the gas generator speed and the compressor inlet air flow rate: The gas generator rotation speed that satisfies the cross-sectional flow velocity limit can then be calculated. This refers to the upper limit of the reliable ignition speed range. Therefore, the reliable ignition speed range can be determined as [ng1, ng2].

[0062] It is understood that this invention first establishes a mapping relationship between the gas generator speed and the compressor inlet air flow rate through compressor component tests. Then, based on the combustion chamber design parameters and the cross-sectional flow velocity limit conditions at the ignition nozzle installation section, the corresponding inlet air flow rate value is calculated. This allows for the calculation of the gas generator speed value that meets the cross-sectional flow velocity limit conditions. Once this gas generator speed value is exceeded, it means that reliable ignition cannot be achieved in the combustion chamber. Since the upper limit value is set based on the component test results and cross-sectional flow velocity limit conditions of the turboshaft engine, it can better match the starting performance and requirements of different turboshaft engine models, ensuring the accuracy and reliability of the reliable ignition speed range.

[0063] In addition, such as Figure 3 As shown, the process of determining the minimum ignition frequency based on the hot start characteristics and the range of reliable ignition speeds includes the following:

[0064] Step S31: Based on the test results of restarting immediately after shutdown, construct the mapping relationship between the gas generator speed acceleration and the gas generator speed;

[0065] Step S32: Substitute the lower limit of the reliable ignition speed range into the mapping relationship to obtain the corresponding gas generator speed acceleration value, and calculate the shortest passage time of the reliable ignition speed range based on the gas generator speed acceleration value;

[0066] Step S33: Based on the shortest passage time and spark quantity constraints within the reliable ignition speed range, the minimum ignition frequency of the turboshaft engine is calculated.

[0067] Specifically, this invention considers the hot-start characteristics of turboshaft engines. Before hot starting, the lubricating oil system is fully preheated, resulting in minimal rotor resistance. Therefore, compared to cold starting, hot starting requires the least time to pass through the reliable ignition speed range [ng1, ng2], and at the same ignition frequency, generates fewer sparks, thus placing more stringent requirements on the start-up process. Therefore, this invention first conducts an engine restart test immediately after shutdown (i.e., a hot-start test, where Tt45 is highest and the time required to pass through the reliable ignition speed range is minimal) on a conventional ground test bench. Based on the test results, the gas generator speed curve ng-t can be obtained. Furthermore, based on the gas generator speed curve ng-t, a mapping relationship between the gas generator speed acceleration and the gas generator speed is constructed, which can be expressed as: .

[0068] This invention takes into account that within the reliable ignition speed range, the gas generator speed acceleration gradually decreases as the gas generator speed increases. To ensure the accuracy of the minimum ignition frequency design and improve the start-up success rate, this invention selects the gas generator speed acceleration corresponding to the lower limit of the reliable ignition speed range. Assuming the time required to accelerate uniformly to the upper limit of the reliable ignition speed range from the lower limit is: This is taken as the shortest passage time t in the reliable ignition speed range.

[0069] Next, based on research and development experience, in order to ensure successful ignition, the number of sparks generated in the reliable ignition speed range should not be less than S. S is generally not less than 3, but the value varies for different engines. Therefore, based on this spark number constraint and the shortest passage time t of the reliable ignition speed range obtained by solving, the minimum ignition frequency of the turboshaft engine can be calculated using the following formula:

[0070] ;

[0071] in, The minimum ignition frequency of the turboshaft engine is represented by t, the shortest transit time within the reliable ignition speed range is represented by , and S represents the number of sparks required for successful ignition within the reliable ignition speed range. This represents the gas generator speed acceleration value corresponding to the lower limit of the reliable ignition speed range in the mapping relationship between gas generator speed acceleration and gas generator speed. This indicates the design value of the airflow percentage on the right side of the ignition nozzle. This indicates the design value of the cross-sectional area of ​​the flame tube at the installation position of the ignition nozzle. Indicates air density, This represents the nozzle inlet pressure value when the Sothel mean diameter condition is met. , , , All are constants.

[0072] It is understandable that during the actual start-up process of a turboshaft engine, when the gas generator speed is within the reliable ignition speed range [ng1, ng2], the ignition frequency within this range should not be less than […]. This ensures successful starting of the turboshaft engine. Based on the hot-start characteristics of turboshaft engines, this invention establishes more stringent minimum ignition frequency requirements, guaranteeing successful starting of the turboshaft engine regardless of whether it is a cold or hot start, thus significantly improving the starting success rate of the turboshaft engine.

[0073] In addition, such as Figure 4 As shown, another embodiment of the present invention also provides a turboshaft engine ignition frequency design system based on hot start characteristics, preferably employing the turboshaft engine ignition frequency design method based on hot start characteristics as described above, including:

[0074] The lower limit setting module is used to determine the nozzle inlet pressure value that meets the Sotelle average diameter condition based on the nozzle atomization test results, and to determine the lower limit value of the reliable ignition speed range based on the nozzle inlet pressure value.

[0075] The upper limit setting module is used to determine the upper limit of the reliable ignition speed range based on the test results of the compressor components and the design parameters of the combustion chamber;

[0076] The minimum ignition frequency calculation module is used to determine the minimum ignition frequency based on the range of values ​​for hot start characteristics and reliable ignition speed range.

[0077] It is understood that the turboshaft engine ignition frequency design system based on hot start characteristics in this embodiment determines the upper and lower limits of the reliable ignition speed range based on the real test data of the turboshaft engine, and determines the minimum ignition frequency in combination with the hot start characteristics of the turboshaft engine. It has stricter starting requirements and can accurately design the minimum ignition frequency corresponding to different models of turboshaft engines. It can better match the starting performance and requirements of different models of turboshaft engines and greatly improve the starting success rate of turboshaft engines.

[0078] In addition, another embodiment of the present invention provides an electronic device including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method described above by calling the computer program stored in the memory.

[0079] In addition, another embodiment of the present invention provides a computer-readable storage medium for storing a computer program for designing the ignition frequency of a turboshaft engine based on hot start characteristics, wherein the computer program executes the steps of the method described above when run on a computer.

[0080] Common computer-readable storage media include: floppy disks, flexible disks, hard disks, magnetic tapes, any other magnetic media, CD-ROMs, any other optical media, punch cards, paper tape, any other physical media with perforated patterns, random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), flash erasable programmable read-only memory (FLASH-EPROM), any other memory chips or cartridges, or any other media readable by a computer. Instructions may further be transmitted or received by a transmission medium. The term transmission medium can include any tangible or intangible medium used to store, encode, or carry instructions for execution by a machine, and includes digital or analog carrier communication signals or intangible media that facilitate communication of such instructions. Transmission media include coaxial cables, copper wires, and optical fibers, which contain conductors for transmitting a bus of computer data signals.

[0081] 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 implemented 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. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0082] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0083] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0084] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0085] 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.

[0086] 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.

[0087] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for designing the ignition frequency of a turboshaft engine based on its hot-start characteristics, characterized in that, Includes the following: Based on the nozzle atomization test results, the nozzle inlet pressure value that meets the Sotelle average diameter condition is determined, and the lower limit of the reliable ignition speed range is determined based on the nozzle inlet pressure value. The upper limit of the reliable ignition speed range is determined based on the test results of the compressor components and the design parameters of the combustion chamber; The minimum ignition frequency is determined based on the hot start characteristics and the range of values ​​for the reliable ignition speed range; The process of determining the minimum ignition frequency based on the hot start characteristics and the range of reliable ignition speed includes the following: Based on the test results of immediate restart after shutdown, a mapping relationship between the gas generator speed acceleration and the gas generator speed is constructed. Substitute the lower limit of the reliable ignition speed range into the mapping relationship to obtain the corresponding gas generator speed acceleration value, and calculate the shortest passage time of the reliable ignition speed range based on the gas generator speed acceleration value. Based on the minimum passage time and spark quantity constraints within the reliable ignition speed range, the minimum ignition frequency of the turboshaft engine is calculated. The minimum ignition frequency of a turboshaft engine is calculated based on the following formula: ； in, The minimum ignition frequency of the turboshaft engine is represented by t, the shortest transit time within the reliable ignition speed range is represented by , and S represents the number of sparks required for successful ignition within the reliable ignition speed range. This represents the gas generator speed acceleration value corresponding to the lower limit of the reliable ignition speed range in the mapping relationship between gas generator speed acceleration and gas generator speed. This indicates the design value of the airflow percentage on the right side of the ignition nozzle. This indicates the design value of the cross-sectional area of ​​the flame tube at the installation position of the ignition nozzle. Indicates air density, This represents the nozzle inlet pressure value when the Sothel mean diameter condition is met. , , , All are constants.

2. The method for designing the ignition frequency of a turboshaft engine based on hot start characteristics as described in claim 1, characterized in that, The process of determining the upper limit of the reliable ignition speed range based on compressor component test results and combustion chamber design parameters includes the following: Based on the test results of the compressor components, a mapping relationship between the gas generator speed and the compressor inlet air flow rate is constructed; The design value of the air flow rate ratio of the right section of the ignition nozzle in the combustion chamber flame tube and the design value of the cross-sectional area of ​​the flame tube at the ignition nozzle installation position are obtained. The corresponding inlet air flow rate value is calculated based on the cross-sectional flow velocity limit condition at the ignition nozzle installation section. Substitute this inlet air flow rate value into the mapping relationship between the gas generator speed and the compressor inlet air flow rate to calculate the gas generator speed value that satisfies the cross-sectional velocity limit condition, and use it as the upper limit of the reliable ignition speed range.

3. The method for designing the ignition frequency of a turboshaft engine based on hot start characteristics as described in claim 2, characterized in that, The inlet air flow rate that satisfies the cross-sectional velocity limitation condition is calculated based on the following formula: ； in, This represents the inlet air flow rate value when the cross-sectional velocity limit condition is met. Indicates air density, This indicates the design value of the cross-sectional area of ​​the flame tube at the installation position of the ignition nozzle. This indicates the design value of the airflow percentage on the right side of the ignition nozzle.

4. The method for designing the ignition frequency of a turboshaft engine based on hot start characteristics as described in claim 1, characterized in that, The shortest transit time within the reliable ignition speed range is calculated based on the following formula: ； Where t represents the shortest transit time within the reliable ignition speed range. This indicates the upper limit of the reliable ignition speed range. This represents the lower limit of the reliable ignition speed range. This represents the gas generator speed acceleration value corresponding to the lower limit of the reliable ignition speed range in the mapping relationship between gas generator speed acceleration and gas generator speed.

5. The method for designing the ignition frequency of a turboshaft engine based on hot start characteristics as described in claim 1, characterized in that, The process of determining the lower limit of the reliable ignition speed range based on the nozzle inlet pressure value includes the following: A whole-machine start-up test was conducted, and the measured values ​​of nozzle inlet pressure and gas generator speed were recorded during the whole-machine test. A mapping relationship between nozzle inlet pressure and gas generator speed was constructed. The nozzle inlet pressure value that meets the Sotelle mean diameter condition was substituted into the mapping relationship to obtain the gas generator speed value that meets the Sotelle mean diameter condition, which was used as the lower limit value of the reliable ignition speed range.

6. A turboshaft engine ignition frequency design system based on hot start characteristics, employing the turboshaft engine ignition frequency design method based on hot start characteristics as described in any one of claims 1 to 5, characterized in that, include: The lower limit setting module is used to determine the nozzle inlet pressure value that meets the Sotelle average diameter condition based on the nozzle atomization test results, and to determine the lower limit value of the reliable ignition speed range based on the nozzle inlet pressure value. The upper limit setting module is used to determine the upper limit of the reliable ignition speed range based on the test results of the compressor components and the design parameters of the combustion chamber; The minimum ignition frequency calculation module is used to determine the minimum ignition frequency based on the range of values ​​for hot start characteristics and reliable ignition speed range.

7. An electronic device, characterized in that, The method includes a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method as described in any one of claims 1 to 5 by calling the computer program stored in the memory.

8. A computer-readable storage medium for storing a computer program for designing the ignition frequency of a turboshaft engine based on hot-start characteristics, characterized in that, The computer program, when run on a computer, performs the steps of the method as described in any one of claims 1 to 5.

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