Aeroengine low temperature start control method and system

Abstract

The application discloses an aero-engine low-temperature starting control method and system, comprising the following steps: S1: collecting the operation parameters and the basic total injection oil amount of the engine, wherein the operation parameters include the ambient temperature of the engine; S2: determining the injection parameters of the combustion-supporting agent according to the collected ambient temperature and performing combustion-supporting agent injection, wherein the injection parameters of the combustion-supporting agent include the starting time of the combustion-supporting agent injection and the duration of the injection; S3: determining the secondary injection parameters of the fuel according to the collected ambient temperature and performing fuel injection. The application can realize the direct starting of the aero-engine in a low-temperature environment of-50 DEG C without the aid of external auxiliary combustion-supporting structures through the cooperation of the secondary injection of the combustion-supporting agent and the fuel, which can simplify the structural arrangement of the aero-engine and greatly expand the use scenarios of the aero-engine.

Description

TECHNICAL FIELD

[0001] The present application relates to an aero-engine control method, in particular to an aero-engine low-temperature starting control method and system. BACKGROUND

[0002] The aero-engine is a kind of highly complex and precise thermal mechanical as the core power device of the aircraft, which can provide necessary thrust and power for the flight of the aircraft. Since the ambient temperature is low when the aircraft is cruising at high altitude, it is difficult to start the aero-engine. At present, the same type of engine on the market can only be started normally at an ambient temperature of-20 DEG C and above without the help of external starting system, and cannot meet the starting under the ambient temperature of specific demand, such as-50 DEG C.

[0003] In order to realize the normal starting of the aero-engine in the low-temperature environment, the Chinese patent document CN105351030A discloses an aero-engine low-temperature starting control device, which comprises a first pipeline, the first pipeline is connected to a second pipeline through a drain pipeline and a fuel supply pipeline respectively, the second pipeline is communicated with a heat preservation oil tank, a circulating pipeline communicated with the heat preservation oil tank is arranged on the second pipeline, and an electric heater for heating the lubricating oil is arranged in the heat preservation oil tank; the drain pipeline, the fuel supply pipeline, the circulating pipeline and the second pipeline are all provided with a switch valve, an oil pump for discharging lubricating oil from the heat preservation oil tank is arranged on the second pipeline, and the control device further comprises a controller for controlling the operation of the electric heater, and the switch valve is controlled by the controller to realize the discharge or supply of the lubricating oil system. The lubricating oil in the lubricating oil system of the engine is heated by the way of lubricating oil replacement, that is, the lubricating oil in the lubricating oil system of the engine is sequentially pumped back to the heat preservation oil tank, and then is sent back to the lubricating oil system of the engine after being heated in the heat preservation oil tank, so that the reliable starting of the aero-engine in low temperature is realized.

[0004] In addition, the Chinese patent document CN1345430A discloses a compact, efficient and rapid fuel storage and heating device and heating method. The heating device mainly consists of a fuel storage device component, a heating ring component, an upper section heat insulation component, a lower section heat insulation component, a left section heat insulation component, a right section heat insulation component, a temperature sensor and the like. The present application is used for directly heating the fuel of the fuel system of the small and medium-sized gas turbine or aero-engine before starting or during operation, has the ability to rapidly heat the fuel in the storage device from low temperature to a specified temperature within a specified time, ensures that the temperature of the fuel stored in the heating device is within a specified temperature range when the gas turbine or aero-engine reaches the fuel supply rotating speed, and can adjust the outlet oil temperature. The present application adjusts the heating temperature of the fuel heating device by adopting heating temperature feedback control, realizes the fuel temperature rise, and at the same time, protects the device from over-temperature, so as to avoid the danger of fuel temperature exceeding the flash point.

[0005] Although the prior art above can realize the smooth starting of the aero-engine in the low-temperature environment, the heating equipment is separately arranged for heating in the starting process, and the structure is complex. Moreover, the existing aero-engine cannot realize the normal starting under the environment temperature of-50 DEG C because the environment temperature of the aircraft can reach-50 DEG C when cruising at high altitude. SUMMARY

[0006] The present application provides a low-temperature starting control method of aero-engine to solve the technical problem of complex structure caused by the heating of the low-temperature starting of the aero-engine in the prior art by means of the heating equipment, and comprises the following steps:

[0007] S1: collecting the operation parameters and the basic total injection oil amount of the engine, and the operation parameters include the environment temperature where the engine is located;

[0008] S2: determining the injection parameters of the combustion-supporting agent according to the collected environment temperature according to formula a and performing the injection of the combustion-supporting agent, and the injection parameters of the combustion-supporting agent include the starting time of the injection of the combustion-supporting agent and the duration of the injection;

[0009] Formula a;

[0010] In formula a, alpha represents the starting time of the injection of the combustion-supporting agent, beta represents the duration of the injection of the combustion-supporting agent, x represents the environment temperature;

[0011] S3: determining the secondary injection parameters of the fuel according to formula b according to the collected environment temperature and performing the injection of the fuel, and the secondary injection parameters include the multiple of the total injection oil amount under the current environment temperature relative to the basic total injection oil amount, the starting time of the first injection, the ending time of the second injection, and the ratio of the first injection amount to the total injection oil amount under the current environment temperature;

[0012] Formula b;

[0013] In formula b, gamma represents the multiple of the total injection oil amount under the current environment temperature relative to the basic total injection oil amount, and the product of gamma and the basic total injection oil amount is the total injection oil amount under the current environment temperature; delta represents the starting time of the first injection, theta represents the ending time of the second injection, and mu represents the ratio of the first injection amount to the total injection oil amount under the current environment temperature.

[0014] In existing technologies, external auxiliary heating equipment is required for starting in low-temperature environments, which complicates the structure of aero engines and limits their application scenarios. This solution, through the combined secondary injection of oxidizer and fuel, enables direct starting of aero engines in low-temperature environments without the need for external auxiliary combustion structures. This simplifies the structural design of aero engines and greatly expands their application scenarios.

[0015] Preferably, in S1, the collected operating parameters also include cylinder head temperature. When the ambient temperature remains constant, the injection parameters of the combustion-supporting agent and the secondary fuel injection parameters are adjusted whenever the cylinder head temperature changes by a preset value. This solution also adjusts the injection parameters of the combustion-supporting agent and the secondary fuel injection parameters based on the cylinder head temperature to improve their accuracy, thereby enabling the aero-engine to start normally in low-temperature environments, and simplifying operation.

[0016] Preferably, the preset change value is 10°C. For every 10°C increase in cylinder head temperature, the start time of the oxidizer injection increases by 0.5 seconds, the duration of the oxidizer injection decreases by 0.5 seconds, the ratio of the total injected fuel quantity at the current ambient temperature to the base total injected fuel quantity decreases by 3.5%, the start time of the first injection is advanced by 10°C, the end time of the second injection is advanced by 10°C, and the ratio of the first injection quantity to the total injected fuel quantity at the current ambient temperature increases by 0.05. This scheme can effectively ensure the normal starting of the aero-engine in low-temperature environments.

[0017] Preferably, in S1, the collected operating parameters also include the engine's power supply voltage and the atmospheric pressure of the engine's environment; in S3, the total fuel injection quantity is corrected based on the collected atmospheric pressure and power supply voltage at the current ambient temperature. This solution can correct the total fuel injection quantity at the current ambient temperature based on the atmospheric pressure and power supply voltage of the aero-engine's current environment, thereby effectively ensuring the normal starting of the aero-engine in low-temperature environments.

[0018] Preferably, in S3, the total amount of fuel injected at the current ambient temperature is corrected according to formula c based on the collected atmospheric pressure and power supply voltage.

[0019] ...Formula c;

[0020] Where π represents the correction factor for the total fuel injection quantity at the current ambient temperature based on atmospheric pressure, y represents atmospheric pressure (unit: kPa), and ε represents the correction factor for the total fuel injection quantity at the current ambient temperature based on the power supply voltage (unit: V). This scheme further improves the accuracy of secondary fuel injection, effectively ensuring the normal starting of the aero-engine in low-temperature environments.

[0021] Preferably, in S1, the operating parameters also include the engine fault code and engine speed. The current operating status of the engine is determined based on these parameters, and a pre-start command is sent and S2 is executed accordingly. This solution can automatically determine whether a low-temperature start operation is needed based on the engine's current operating status, ensuring timely start-up and thus guaranteeing the normal flight of the aircraft engine.

[0022] Preferably, in step S2, the injection starts within a preset time period after the pre-start command is issued. In this solution, setting the start time of the combustion-supporting agent injection after the pre-start command is issued avoids the waste of the combustion-supporting agent.

[0023] Preferably, in step S2, a start-up command is sent after the oxidizer injection is completed, and step S3 is executed. This solution can effectively ensure the normal start-up of the aero-engine in low-temperature environments.

[0024] Secondly, the present invention also provides a cryogenic start-up control system for an aero-engine, including a data acquisition module for acquiring engine operating parameters and basic total fuel injection quantity, a determination module for determining the engine's operating state, and an execution module for executing oxidizer injection and fuel injection. The data acquisition module and the execution module control the cryogenic start-up of the aero-engine according to the aforementioned cryogenic start-up control method for an aero-engine.

[0025] The present invention has the following beneficial effects:

[0026] This invention enables direct starting of aero engines in a low-temperature environment of -50°C without the aid of external auxiliary combustion structures by combining secondary injection of combustion-supporting agent and fuel. On the one hand, it simplifies the structural design of aero engines, and on the other hand, it greatly expands the application scenarios of aero engines. Attached Figure Description

[0027] Figure 1 This is a flowchart illustrating the control method in an embodiment of the low-temperature start-up control method and system for aero-engines of the present invention.

[0028] Figure 2 This is a block diagram of the control system in the embodiment of the low-temperature start-up control method and system for aero-engines of the present invention. Detailed Implementation

[0029] The following detailed description illustrates the specific implementation method:

[0030] 1. Definition

[0031] Fault codes are specific codes generated when an engine malfunctions. They are used to locate the faulty component and type. Different fault codes correspond to different fault categories and solutions.

[0032] Combustion improver: An aviation fuel additive that can improve the efficiency of aviation fuel and reduce pollution emissions. Its working principle is to improve the combustion process of fuel and thus improve fuel efficiency.

[0033] 2. The basic implementation method is as shown in the attached figure. Figure 1 and Figure 2 The following steps are shown: A method for controlling the cryogenic start-up of an aircraft engine.

[0034] S1: Collect engine operating parameters and basic total injection fuel quantity and determine the current operating status of the engine.

[0035] The system collects engine operating parameters and basic total fuel injection quantity. Operating parameters include cylinder head temperature, atmospheric pressure, power supply voltage, engine speed, fuel pressure, ambient temperature of the engine, and engine fault codes. Based on the collected fault codes, engine speed, power supply voltage, and fuel pressure, the system determines the engine's operating status and confirms whether a pre-start command needs to be issued.

[0036] Since the engine can start normally without the aid of an external starting system at an ambient temperature of -20℃, meaning that the total fuel injection quantity at an ambient temperature of -20℃ can be obtained during the engine starting process, this solution sets the total fuel injection quantity at an ambient temperature of -20℃ as the base total fuel injection quantity.

[0037] When determining the engine's operating status, if the engine fault code, engine speed, power supply voltage, and fuel pressure meet preset judgment conditions, a pre-start command is issued. In this embodiment, if all four conditions are met—no engine fault code, engine speed ≤ 100 r / min, power supply voltage between 10.5V and 14V, and fuel pressure > 0.5 bar—it is determined that the preset judgment conditions are met, a pre-start command is issued, and S2 is executed.

[0038] S2. Upon receiving the pre-start command, determine the injection parameters of the combustion-supporting agent based on the collected cylinder head temperature and ambient temperature, and then inject the combustion-supporting agent.

[0039] Because the lower the ambient temperature, the less fuel is actually produced and the worse the fuel atomization is under the same injection pulse width, the longer the continuous injection time of the combustion improver is required. However, if the fuel injection and combustion improver injection overlap for a long time, it will lead to large differences in combustion between engine cycles, resulting in large fluctuations in engine speed.

[0040] Therefore, when determining the injection parameters of the combustion improver, in order to ensure that the duration of the combustion improver injection meets the engine starting requirements and the engine operates normally after fuel injection, the collected ambient temperature is first used to determine the start time and duration of the combustion improver injection according to formula a and then allocated.

[0041] ...Formula a;

[0042] In formula a, α represents the start time of the combustion-supporting agent injection, and β represents the duration of the combustion-supporting agent injection. x Indicates ambient temperature.

[0043] Then, with the ambient temperature constant, the injection parameters of the combustion-supporting agent are adjusted whenever the cylinder head temperature changes by a preset value. Specifically, when the cylinder head temperature increases by 10°C, the start time of the combustion-supporting agent injection increases by 0.5 seconds, and the duration of the combustion-supporting agent injection decreases by 0.5 seconds.

[0044] In this embodiment, when the ambient temperature is between -50℃ and -20℃, and the corresponding cylinder head temperature is between -50℃ and -20℃, the start time of the oxidizer injection is within 0s to 1.5s after the pre-start command is issued, and the duration of the oxidizer injection is between 1.5s and 3s. The specific results are shown in Tables 1 and 2.

[0045] Table 1. Relationship between the initiation time of combustion-supporting agent injection and ambient temperature and cylinder head temperature.

[0046]

[0047] In Table 1, with the ambient temperature remaining constant, the initiation time of the combustion-supporting agent injection increases by 0.5 seconds for every 10°C increase in cylinder head temperature.

[0048] Table 2. Relationship between the duration of combustion-supporting agent injection and ambient temperature and cylinder head temperature.

[0049]

[0050] In Table 2, with the ambient temperature remaining constant, the duration of the combustion-supporting agent injection decreases by 0.5 seconds for every 10°C increase in cylinder head temperature.

[0051] After the combustion-supporting agent injection is completed, a start command is sent and S3 is executed.

[0052] S3. Upon receiving the start command, determine the secondary fuel injection parameters based on the collected cylinder head temperature, ambient temperature, atmospheric pressure, and power supply voltage, and then perform fuel injection.

[0053] Because lower ambient temperatures result in less fuel output and poorer fuel atomization for the same injection pulse width, a larger amount of fuel is required. The later the start and end times of the first and second injections, the more fuel remains in the combustion chamber during scavenging. However, too late an injection will reduce the actual fuel injected into the cylinder due to higher cylinder pressure. Therefore, while the start and end times of the first and second injections should be later as ambient temperatures decrease, they must be controlled within a certain range. Lower ambient temperatures also lead to poorer fuel atomization. Once a certain amount of fuel is injected in a single injection, it's impossible to achieve sufficient atomization by increasing the injection amount. Therefore, two injections are needed to control the amount of fuel injected in a single injection. Since the first injection is earlier, allowing more time for a more homogeneous mixture to form, the amount of fuel injected in the first injection should be higher than that injected in the second injection, provided it does not exceed the single injection limit.

[0054] When determining the secondary injection parameters of fuel, the collected ambient temperature is used to determine the multiple of the total injection amount at the current ambient temperature relative to the base total injection amount, the start time of the first injection, the end time of the second injection, and the ratio of the first injection amount to the total injection amount at the current ambient temperature, according to formula b.

[0055] ...Formula b;

[0056] In formula b, γ represents the ratio of the total injection amount at the current ambient temperature to the base total injection amount, and the product of γ and the base total injection amount is the total injection amount at the current ambient temperature; δ represents the start time of the first injection, θ represents the end time of the second injection, and μ represents the ratio of the first injection amount to the total injection amount at the current ambient temperature.

[0057] Then, with the ambient temperature constant, the secondary fuel injection parameters are adjusted whenever the cylinder head temperature changes by a preset value. Specifically, when the cylinder head temperature increases by 10°C, the ratio of the total fuel injection quantity to the base total fuel injection quantity at the current ambient temperature decreases by 3.5%, the start time of the first injection is advanced by 10°C, the end time of the second injection is advanced by 10°C, and the amount of the first injection increases by 0.05% of the total fuel injection quantity at the current ambient temperature.

[0058] Specifically, in this embodiment, when performing secondary fuel injection, when the ambient temperature is between -50℃ and -20℃, and the corresponding cylinder head temperature is also between -50℃ and -20℃, the total fuel injection quantity at the current ambient temperature is between 10mg / cycle and 20mg / cycle. The ratio of the first fuel injection quantity to the total fuel injection quantity at the current ambient temperature is between 60% and 90%. The first fuel injection starts between 130° and 220° before the piston reaches top dead center, and the second fuel injection ends between 40° and 70° before top dead center. Specific results are shown in Tables 3, 4, 5, and 6.

[0059] Table 3. Relationship between the ratio of total injection quantity to base total injection quantity at current ambient temperature and ambient temperature and cylinder head temperature.

[0060]

[0061] In Table 3, under constant ambient temperature, for every 10°C increase in cylinder head temperature, the ratio of the total injection amount to the base total injection amount at the current ambient temperature decreases by 3.5%.

[0062] Table 4. Relationship between the start time of the first fuel injection and ambient temperature and cylinder head temperature

[0063]

[0064] In Table 4, under the condition that the ambient temperature remains unchanged, for every 10°C increase in cylinder head temperature, the start time of the first fuel injection is advanced by 10°C.

[0065] Table 5 Relationship between the end time of the second fuel injection and ambient temperature and cylinder head temperature

[0066]

[0067] In Table 5, under constant ambient temperature, for every 10°C increase in cylinder head temperature, the second injection end time is advanced by 10°C.

[0068] Table 6. Relationship between the ratio of the first injection quantity to the total injection quantity at the current ambient temperature and ambient temperature and cylinder head temperature.

[0069]

[0070] In Table 6, under constant ambient temperature, for every 10°C increase in cylinder head temperature, the ratio of the first injection amount to the total injection amount at the current ambient temperature increases by 0.05.

[0071] As the ECU voltage increases, the cross-sectional area of ​​the fuel injector outlet increases, leading to an increase in the actual fuel injection quantity. Furthermore, as atmospheric pressure decreases, the fuel injection quantity should also decrease due to the reduced air density. Therefore, the total fuel injection quantity at the current ambient temperature is corrected based on the collected atmospheric pressure and power supply voltage. Specifically, the total fuel injection quantity at the current ambient temperature is corrected sequentially according to formula c based on the collected atmospheric pressure and power supply voltage.

[0072] ...Formula c;

[0073] Where π represents the correction factor for the total fuel injection quantity under the current ambient temperature based on atmospheric pressure, y represents atmospheric pressure (in kPa), ε represents the correction factor for the total fuel injection quantity under the current ambient temperature based on the power supply voltage, and z represents the power supply voltage (in V).

[0074] Specifically, when the atmospheric pressure is between 45 kPa and 103 kPa, the total fuel injection quantity at the current ambient temperature is corrected based on 10 mg / cycle to 20 mg / cycle, with a correction factor between 0.5 and 1. Furthermore, when the power supply voltage is between 10.5 V and 14 V, the total fuel injection quantity at the current ambient temperature will be further corrected, with a correction factor between 0.85 and 1.15.

[0075] Based on the above-mentioned low-temperature start control method for aero-engines, this embodiment also discloses a low-temperature start control system for aero-engines, including a data acquisition module for collecting engine operating parameters and basic total fuel injection quantity, a determination module for determining the engine's operating state, and an execution module for executing oxidizer injection and fuel injection.

[0076] The acquisition module collects operating parameters including engine fault codes, engine speed, fuel pressure, power supply voltage, atmospheric pressure, cylinder head temperature, and the ambient temperature of the engine. Engine fault codes can include those related to rail pressure, etc.

[0077] The determination module determines the current operating status of the engine based on the collected operating parameters, in order to determine whether to execute steps S2 and S3.

[0078] During the judgment, the preset judgment conditions are that the engine has no fault codes, the engine speed is ≤100r / min, the power supply voltage is between 10.5V and 14V, and the fuel pressure is >0.5bar. If all four conditions are met, it can be determined that steps S2 and S3 can be executed.

[0079] The execution module performs the combustion-supporting agent injection operation in S2 and the secondary fuel injection operation in S3 based on the collected operating parameters.

[0080] Specifically, the oxidizer injection operation in S2 is as follows: when the ambient temperature is between -50℃ and -20℃, and the corresponding cylinder head temperature is between -50℃ and -20℃, the oxidizer injection starts within 0s to 1.5s after the pre-start command is issued, and the oxidizer injection duration is between 1.5s and 3s. After the oxidizer injection is completed, a start command is sent, and S3 is executed.

[0081] The secondary fuel injection operation in S3 is as follows: when the ambient temperature is between -50℃ and -20℃, and the corresponding cylinder head temperature is between -50℃ and -20℃, the total fuel injection quantity at the current ambient temperature is between 10mg / cycle and 20mg / cycle, the ratio of the first fuel injection quantity to the total fuel injection quantity is between 90% and 60%, the first fuel injection starts between 130° and 220° before the piston reaches top dead center, and the second fuel injection ends between 40° and 70° before top dead center.

[0082] When the atmospheric pressure is between 45 kPa and 103 kPa, the total fuel injection quantity at the current ambient temperature is corrected based on 10 mg / cycle to 20 mg / cycle, with a correction factor between 0.5 and 1. Furthermore, when the power supply voltage is between 10.5 V and 14 V, the total fuel injection quantity at the current ambient temperature will be further corrected, with a correction factor between 0.85 and 1.15.

[0083] In the specific implementation process, three aero engines were used: No. 1 (using electronic control unit and port injection), No. 2 (using electronic control unit and direct injection), and No. 3 (using electronic control unit, direct injection, oxidizer injection system, and secondary fuel injection strategy). Start-up tests were conducted in a cold storage at ambient temperatures of -10℃, -20℃, -30℃, and -50℃. Before starting, each engine was left to stand at these temperatures for 8 hours. The criterion for successful start-up was that there were 3 consecutive starts, with one engine successfully igniting and burning for more than 10 seconds. The results are shown in Table 7.

[0084] Table 7 Comparison Results of Low Temperature Start-up

[0085]

[0086] As shown in Table 7, the low-temperature start-up control method for aero-engines of the present invention can ensure that aero-engines can start directly without the aid of external auxiliary equipment at an ambient temperature of -50℃, which greatly expands the user's application scenarios.

[0087] The above descriptions are merely embodiments of the present invention. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for controlling the cryogenic start-up of an aircraft engine, comprising the following steps: S1: Collect the engine's operating parameters and basic total injection fuel quantity, including the ambient temperature where the engine is located; Its features are: S2. The collected ambient temperature is used to determine the injection parameters of the combustion accelerator according to formula a and the combustion accelerator is injected. The injection parameters of the combustion accelerator include the start time of the combustion accelerator injection and the duration of the injection. ...Formula a; In formula a, α represents the start time of the oxidizer injection, with the unit of start time being seconds (s), and β represents the duration of the oxidizer injection, with the unit of duration being seconds (s). x This indicates the ambient temperature, which is expressed in °C. S3. The collected ambient temperature is used to determine the secondary fuel injection parameters according to formula b and fuel injection is performed. The secondary injection parameters include the multiple of the total fuel injection amount under the current ambient temperature relative to the basic total fuel injection amount, the start time of the first fuel injection, the end time of the second fuel injection, and the ratio of the first fuel injection amount to the total fuel injection amount under the current ambient temperature. ...Formula b; In formula b, γ represents the ratio of the total fuel injection amount at the current ambient temperature to the base total fuel injection amount. The product of γ and the base total fuel injection amount is the total fuel injection amount at the current ambient temperature, and the unit of total fuel injection amount is mg / cycle; δ represents the start time of the first fuel injection, and the unit of the start time of the first fuel injection is °; θ represents the end time of the second fuel injection, and the unit of the end time of the second fuel injection is °; μ represents the ratio of the first fuel injection amount to the total fuel injection amount at the current ambient temperature.

2. The method for controlling the cryogenic start-up of an aero-engine according to claim 1, characterized in that: In S1, the collected operating parameters also include cylinder head temperature. When the ambient temperature remains constant, the injection parameters of the combustion-supporting agent and the secondary injection parameters of the fuel are adjusted whenever the cylinder head temperature changes by a preset value.

3. The method for controlling the cryogenic start-up of an aero-engine according to claim 2, characterized in that: The preset value for the change is 10°C. When the cylinder head temperature increases by 10°C, the start time of the combustion-supporting agent injection increases by 0.5s, the duration of the combustion-supporting agent injection decreases by 0.5s, the ratio of the total injection amount at the current ambient temperature to the base total injection amount decreases by 3.5%, the start time of the first injection is advanced by 10°, the end time of the second injection is advanced by 10°, and the ratio of the first injection amount to the total injection amount at the current ambient temperature increases by 0.

05.

4. The method for controlling the cryogenic start-up of an aero-engine according to any one of claims 1-3, characterized in that: In S1, the collected operating parameters also include the engine's power supply voltage and the atmospheric pressure of the engine's environment. In S3, the total amount of fuel injected at the current ambient temperature is corrected based on the collected atmospheric pressure and power supply voltage.

5. The method for controlling the cryogenic start-up of an aero-engine according to claim 4, characterized in that: In S3, the total amount of fuel injected at the current ambient temperature is corrected according to formula c based on the collected atmospheric pressure and power supply voltage. ...Formula c; Where π represents the correction factor for the total fuel injection quantity under the current ambient temperature based on atmospheric pressure, y represents atmospheric pressure (in kPa), ε represents the correction factor for the total fuel injection quantity under the current ambient temperature based on the power supply voltage, and z represents the power supply voltage (in V).

6. The method for controlling the cryogenic start-up of an aero-engine according to claim 5, characterized in that: In S1, the operating parameters also include the engine fault code and engine speed. The current working state of the engine is determined based on the operating parameters, and a pre-start command is sent according to the working state and S2 is executed.

7. The method for controlling the cryogenic start-up of an aero-engine according to claim 6, characterized in that: In S2, the injection starts within a preset time period after the pre-start command is issued.

8. The method for controlling the cryogenic start-up of an aero-engine according to claim 7, characterized in that: In S2, after the combustion-supporting agent injection is completed, a start command is sent, and S3 is executed.

9. A cryogenic start-up control system for an aircraft engine, characterized in that: The system includes a data acquisition module for collecting the engine's operating parameters and basic total fuel injection quantity, a determination module for determining the engine's operating status, and an execution module for performing oxidizer injection and fuel injection. The data acquisition module, the determination module, and the execution module control the low-temperature start-up of the aero-engine according to any one of claims 1-8.

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