A starting control system and method for suppressing starting overshoot of a regenerative cycle engine

Abstract

A starting control system and method for suppressing overshoot of starting of a supplementary combustion cycle engine belongs to the field of automation technology. The present invention includes a flow regulator and a transfer valve located on a fuel pipeline. The flow regulator and the transfer valve are connected by a pipeline and are located on a fuel secondary line in an engine system. The inlet of the flow regulator is connected to the outlet of a secondary fuel pump, and the outlet of the transfer valve is connected to the inlet of a gas generator. The transfer valve is used to control the flow entering the gas generator in the early and middle stages of the engine starting process, and the flow regulator is used to control the flow entering the gas generator in the final stage of the engine starting process. During the entire starting process, the sum of the flow resistance coefficients of the transfer valve and the flow regulator is always higher than the steady-state value under rated conditions. The starting control system of the present invention has a simple composition and high reliability.

Description

Technical Field

[0001] The invention relates to a starting control system and method for suppressing starting overshoot of a supplementary combustion cycle engine, belonging to the technical field of automation. Background Art

[0002] The performance of components of high-thrust regenerative cycle engines under rated operating conditions has been explored to the extreme, and the thermal and mechanical environments of the components are close to critical conditions. If the engine operating conditions are significantly higher than the rated conditions during the starting process, the engine structure will be damaged. Therefore, it is required that the engine operating conditions should not be seriously overshot (≯5%) during the starting process.

[0003] In order to solve the problem of how to suppress the overshoot of the start of the large thrust regenerative cycle engine, the existing YF-100 engine adopts the measures of using a high-pressure starting tank and a flow regulator. The high-pressure starting tank is used to keep the flow regulator in a steady flow working state throughout the engine start process. The flow regulator in this state has the functions of steady flow and level change: the former compensates for the influence of the pressure difference change on the flow by changing the throttling area of ​​the steady flow window through the passive movement of the slide valve in the flow regulator, thereby achieving basic flow stability; the latter adjusts the flow by actively changing the flow area of ​​the throttling window to achieve the function of flow level change. The specific method of suppressing the overshoot of the engine start is: using the flow level change function of the flow regulator to control the gradual rise of the engine working condition; using the movement of the slide valve to increase the flow resistance of the flow regulator when approaching the rated working condition, so that the working condition smoothly transitions to the rated working condition.

[0004] Since the flow regulator needs to reach a certain pressure drop at the inlet and outlet before it can be in a steady-flow working state, the above method needs to be used in conjunction with the use of a high-pressure starting tank when suppressing starting overshoot, that is, an external energy source is used in the early stage of engine starting to provide the conditions for the high pressure drop in the steady-flow working state of the flow regulator. Summary of the invention

[0005] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art, to provide a starting control system and method for suppressing starting overshoot of a regenerative cycle engine, to partially improve the existing flow regulator, and to cooperate with a transfer valve to be arranged on the engine fuel bypass to control the flow entering the gas generator, and then to control the engine operating condition climbing rate, and to effectively suppress the operating condition overshoot occurring during the starting process of the regenerative cycle engine without the aid of any external energy source.

[0006] The technical solution of the present invention is: a starting control system for suppressing overshoot of starting of a supplemental combustion cycle engine, including a flow regulator and a transfer valve located on a fuel pipeline; the flow regulator and the transfer valve are connected by a pipeline and are located on a fuel auxiliary line in the engine system, the inlet of the flow regulator is connected to the outlet of a secondary fuel pump, and the outlet of the transfer valve is connected to the inlet of a gas generator, the transfer valve is used to control the flow entering the gas generator in the early and middle stages of the engine starting process, and the flow regulator is used to control the flow entering the gas generator in the late stage of the engine starting process, and during the entire starting process, the sum of the flow resistance coefficients of the transfer valve and the flow regulator is always higher than the steady-state value under rated conditions.

[0007] Further, the stage transfer valve comprises a diaphragm, a lock pin, a spring and a valve core;

[0008] The diaphragm is located below the lock pin and is used to limit the movement of the lock pin in a small opening state;

[0009] The lock pin is embedded in the valve core and is used to limit the movement of the valve core in the initial state of a small opening;

[0010] The spring is located in the damping chamber between the valve housing and the valve core, and is used to provide damping for the movement of the valve core;

[0011] The valve core and the valve housing are in sliding cooperation and are used to adjust the flow area of ​​the step-changing valve.

[0012] Furthermore, a damping pin is provided in the valve core for discharging the medium in the damping chamber; the aperture of the damping pin is small enough so that the flow area of ​​the step-changing valve increases slowly.

[0013] Furthermore, the step-change valve is provided with a pressure-introducing hole for introducing high-pressure medium into the diaphragm.

[0014] Further, the flow regulator includes a throttling window, a slide valve, a steady flow window and a spring;

[0015] The throttling window is located on the main flow channel at the inlet of the flow regulator, connected to the shell, and has a fixed flow area, and is used to create a pressure difference on both sides of the slide valve;

[0016] The slide valve is installed on the steady flow window and is used to cover part of the steady flow window;

[0017] The steady flow window is located on the main flow channel at the outlet of the flow regulator, connected to the shell, and the flow area is adjusted by the blocking amount of the slide valve;

[0018] The spring is located between the slide valve and the steady flow window and is used to fix the slide valve at an initial position.

[0019] Furthermore, the slide valve and the steady flow window are in sliding fit.

[0020] Furthermore, the flow regulator is provided with a damping hole for introducing the high-pressure medium into the right side of the slide valve; the aperture of the damping hole is large enough so that the displacement of the slide valve has a rapid response capability to the change of the inlet and outlet pressure difference.

[0021] A control method for suppressing starting overshoot of a regenerative combustion cycle engine according to a starting control system for suppressing starting overshoot of a regenerative combustion cycle engine comprises:

[0022] In the early stage of the engine starting process, the valve core of the transfer valve is locked by the lock pin, the transfer valve is initially in a small opening state, and the flow regulator is in an unadjusted state. At this time, the slide valve is pressed against the housing by the spring, and the steady flow window is in a state of maximum flow area;

[0023] As the engine working condition increases, the inlet pressure of the flow regulator increases. After the diaphragm is squeezed by the high-pressure medium, the valve core moves to the damping chamber under the action of the inlet pressure, the damping chamber pressure and the spring force. As a result, the flow area of ​​the transfer valve gradually increases, thereby controlling the flow entering the gas generator to increase steadily and rapidly in the early and middle stages of the engine starting process.

[0024] When the engine operating condition climbs to near the rated condition, the pressure drop of the throttle window exceeds the design threshold, and the slide valve begins to move toward the outlet side under the action of the inlet pressure, the intermediate chamber pressure and the spring force. The movement rate is positively correlated with the pressure drop of the throttle window, and the flow area of ​​the steady flow window is therefore reduced, thereby stabilizing the fuel flow entering the gas generator at the end of the engine starting process.

[0025] Furthermore, before being assembled to the engine, a separate fluid flow action test of the starting control system is conducted, and the test target of a flow overshoot of no more than 5% is achieved by adjusting the apertures of the damping hole and the damping pin.

[0026] Furthermore, in the fluid action test of the starting control system, the inlet and outlet pressure environment is the same as the test run environment.

[0027] The advantages of the present invention compared with the prior art are:

[0028] (1) The starting control system of the present invention is simple in composition and highly reliable. The starting system of the existing launch vehicle main power oxygen-rich regenerative cycle engine includes a flow regulator, a motor, a starting box, a fuel auxiliary valve, a one-way valve, etc., while the present invention only uses a transfer valve and a flow regulator to achieve smooth engine starting, and the system is simple and highly reliable.

[0029] (2) The start-up control system of the present invention does not require external timing control. In the present invention, both the stage transfer valve and the flow regulator are hydraulic valves, and the stage transfer signal of the stage transfer valve is given by the inlet pressure, which does not require external timing control and is easy to use.

[0030] (3) The starting control system of the present invention is highly robust. In the present invention, the switching rate of the switching valve is affected by the inlet and outlet pressures, and the movement process of the flow regulator is only related to the change of the inlet and outlet pressure difference, thereby coupling the movement process of the switching valve and the flow regulator with the engine operating conditions, thereby enhancing the adaptability of the valve movement process to the engine starting process. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the system composition of the present invention;

[0032] Figure 2 The figure is a comparison diagram of the engine starting dimensionless speed calculation curve before and after using the starting control method of the present invention;

[0033] Figure 3 The figure is a curve diagram of the change of flow resistance coefficient of the transfer valve and flow regulator during the engine starting process. DETAILED DESCRIPTION

[0034] In order to better understand the above technical scheme, the technical scheme of the present application is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical scheme of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0035] The following is a further detailed description of a starting control system and method for suppressing overshoot of a regenerative cycle engine starting provided by an embodiment of the present application in conjunction with the accompanying drawings. The specific implementation method may include (eg Figures 1 to 3 As shown): a flow regulator 2 and a transfer valve 12 located on the fuel pipeline; the flow regulator 2 and the transfer valve 12 are connected by a pipeline 16, which are located on the fuel auxiliary line of the engine system, the inlet of the flow regulator 2 is connected to the outlet of the secondary fuel pump, and the outlet of the transfer valve 12 is connected to the inlet of the gas generator. The transfer valve 12 is used to control the flow entering the gas generator in the early and middle stages of the engine starting process, and the flow regulator 2 is used to control the flow entering the gas generator in the final stage of the engine starting process. During the entire starting process, the sum of the flow resistance coefficients of the transfer valve 12 and the flow regulator 2 is always higher than the steady-state value under rated conditions.

[0036] Further, in a possible implementation, the transfer valve 12 includes a diaphragm 10, a lock pin 11, a spring 13 and a valve core 15; the diaphragm 10 is located below the lock pin 11, and is used to limit the movement of the lock pin 11 in a small opening state; the lock pin 11 is embedded in the valve core, and is used to limit the movement of the valve core 15 in an initial small opening state; the spring 13 is located in a damping chamber 14 between the valve housing and the valve core 15, and is used to provide damping for the movement of the valve core 15; the valve core 15 and the valve housing are in a sliding fit, and are used to adjust the flow area of ​​the transfer valve 12.

[0037] In a possible implementation, a damping pin 8 is provided in the valve core 15 for discharging the medium in the damping chamber 14 ; the aperture of the damping pin is small enough so that the flow area of ​​the step-changing valve 12 increases slowly.

[0038] Optionally, in a possible implementation, a pressure-introducing hole 9 is provided in the step-changing valve 12 for introducing a high-pressure medium into the diaphragm 10 .

[0039] Further, in a possible implementation, the flow regulator 2 includes a throttling window 7, a sliding valve 4, a steady flow window 5 and a spring 6; the throttling window 7 is located on the main flow channel at the inlet of the flow regulator 2, connected to the shell, and has a fixed flow area, and is used to create a pressure difference on both sides of the sliding valve 4; the sliding valve 4 is installed on the steady flow window 5, and is used to block part of the steady flow window; the steady flow window 5 is located on the main flow channel 3 at the outlet of the flow regulator 2, and is connected to the shell, and the flow area is adjusted by the blocking amount of the sliding valve 4; the spring 6 is located between the sliding valve 4 and the steady flow window 5, and is used to fix the sliding valve 4 in the initial position.

[0040] Optionally, in a possible implementation, the slide valve 4 and the steady flow window 5 are in sliding fit.

[0041] Furthermore, the flow regulator 2 is provided with a damping hole 1 for introducing the high-pressure medium into the right side of the slide valve 4; the aperture of the damping hole is large enough so that the displacement of the slide valve 4 has a rapid response capability to the change of the inlet and outlet pressure difference.

[0042] Based on Figure 1 The same inventive concept, in order to suppress the operating condition overshoot phenomenon that is easy to occur during the starting process of the regenerative cycle engine, the present invention also proposes a method for jointly controlling the transfer valve and the flow regulator based on the starting control system for suppressing the starting overshoot of the regenerative cycle engine, the steps are as follows:

[0043] (1) When the engine is in the early and middle stages of the starting process, the flow regulator 2 is in an unregulated state, and the flow area of ​​the steady flow window 5 remains unchanged, which acts as a fixed throttle ring. During this stage, the component that controls the growth rate of the fuel flow entering the gas generator is the transfer valve 12. As the transfer valve core 15 is unlocked, the flow area gradually increases, thereby controlling the fuel flow entering the gas generator to increase steadily and rapidly, and the engine operating condition thus rises rapidly.

[0044] (2) When the engine operating condition is close to the rated condition, on the one hand, the flow regulator 2 transitions from the unregulated state to the steady flow working state, and the slide valve 4 starts to move under the action of the inlet and outlet pressures and the spring force, resulting in a gradual decrease in the flow area of ​​the steady flow window 5 and an increase in the flow resistance coefficient; on the other hand, the flow resistance coefficient of the transfer valve 12 continues to decrease. In terms of system parameters, the pressure drop on the transfer valve 12 is gradually transferred to the flow regulator 2. During the pressure drop transfer process, the component design requirements are used to ensure that the sum of the flow resistance coefficients of the transfer valve 12 and the flow regulator 2 is not lower than the steady-state value under the rated condition, thereby stabilizing the fuel flow entering the gas generator, and the engine operating condition gradually transitions to the rated condition.

[0045] Optionally, before being assembled to the engine, a separate fluid flow action test of the starting control system is performed, and the test target of a flow overshoot of no more than 5% is achieved by adjusting the apertures of the damping hole 1 and the damping pin 8 .

[0046] Furthermore, in the fluid action test of the starting control system, the inlet and outlet pressure environment is the same as the test run environment.

[0047] The measure for solving the problem of no external energy in the present invention is to use the transfer valve 12 to control the starting rate of the engine when the flow regulator 2 is in the unregulated state; the measure for suppressing the engine starting overshoot is to limit the reduction rate of the flow resistance coefficient of the transfer valve 2 within a specific time period so as to create a better pressure environment for the flow regulator 2 starting transition process, thereby relying on the rapid response characteristics of the flow regulator slide valve 4 to suppress the engine starting overshoot.

[0048] The control method proposed in the present invention has been verified by simulating the engine starting process. A dynamic simulation model is established for the starting process of the regenerative cycle engine to which the control method is applied, and the calculation results are as follows: Figure 2 As shown in Figure 1, after adopting this control method, the starting overshoot of the engine is reduced from 26% to 3%, achieving the purpose of suppressing the overshoot of the working condition. Among them, the flow resistance coefficient change curve of the transfer valve and the flow regulator is shown in Figure 1. Figure 3As shown in the figure, it can be seen that the flow resistance characteristics of the transfer valve and the flow regulator meet the design requirements, and the sum of the flow resistance coefficients is always guaranteed to be no less than the steady-state value under the rated working condition during the pressure drop transfer process. The engine start simulation calculation results show that the control method proposed in the present invention can effectively suppress the start-up overshoot of the regenerative cycle engine without the help of external energy.

[0049] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

[0050] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A starting control system for suppressing overshoot of starting of a regenerative cycle engine, characterized in that: The invention comprises a flow regulator (2) and a transfer valve (12) located on a fuel pipeline; the flow regulator (2) and the transfer valve (12) are connected via a pipeline (16) and are located on a fuel secondary pipeline of an engine system; an inlet of the flow regulator (2) is connected to an outlet of a secondary fuel pump; an outlet of the transfer valve (12) is connected to an inlet of a gas generator; the transfer valve (12) is used to control a flow rate entering the gas generator in the early and middle stages of an engine starting process; the flow regulator (2) is used to control a flow rate entering the gas generator in the final stage of an engine starting process; and during the entire starting process, the sum of the flow resistance coefficients of the transfer valve (12) and the flow regulator (2) is always higher than a steady-state value under rated operating conditions.

2. A starting control system for suppressing starting overshoot of a regenerative cycle engine according to claim 1, characterized in that: The step-changing valve (12) comprises a diaphragm (10), a lock pin (11), a spring (13) and a valve core (15); The diaphragm (10) is located below the lock pin (11) and is used to limit the movement of the lock pin (11) in a small opening state; The lock pin (11) is embedded in the valve core and is used to limit the movement of the valve core (15) in an initial state of a small opening; The spring (13) is located in a damping chamber (14) between the valve housing and the valve core (15), and is used to provide damping for the movement of the valve core (15); The valve core (15) and the valve housing are in sliding engagement with each other and are used to adjust the flow area of ​​the step-changing valve (12).

3. A starting control system for suppressing starting overshoot of a regenerative cycle engine according to claim 2, characterized in that: The valve core (15) is provided with a damping pin (8) for discharging the medium in the damping chamber (14); The aperture of the damping pin is small enough so that the flow area of ​​the step-changing valve (12) increases slowly.

4. A starting control system for suppressing starting overshoot of a regenerative cycle engine according to claim 2, characterized in that: The step-change valve (12) is provided with a pressure-introducing hole (9) for introducing a high-pressure medium into the diaphragm (10).

5. A starting control system for suppressing starting overshoot of a regenerative cycle engine according to claim 2, characterized in that: The flow regulator (2) comprises a throttling window (7), a slide valve (4), a flow stabilization window (5) and a spring (6); The throttling window (7) is located on the main flow channel at the inlet of the flow regulator (2), is connected to the housing, has a fixed flow area, and is used to create a pressure difference on both sides of the slide valve (4); The slide valve (4) is installed on the steady flow window (5) and is used to cover part of the steady flow window; The steady flow window (5) is located on the main flow channel at the outlet of the flow regulator (2), is connected to the shell, and adjusts the flow area by the blocking amount of the slide valve; The spring (6) is located between the slide valve (4) and the steady flow window (5), and is used to fix the slide valve (4) in an initial position.

6. A starting control system for suppressing starting overshoot of a regenerative cycle engine according to claim 5, characterized in that: The slide valve (4) and the flow stabilizing window (5) are in sliding fit.

7. A starting control system for suppressing starting overshoot of a regenerative cycle engine according to claim 5, characterized in that: The flow regulator (2) is provided with a damping hole (1) for introducing a high-pressure medium into the right side of the slide valve (4); the diameter of the damping hole is large enough so that the displacement of the slide valve (4) has a rapid response capability to changes in the inlet and outlet pressure difference.

8. The control method for suppressing starting overshoot of a regenerative combustion cycle engine implemented by a starting control system for suppressing starting overshoot of a regenerative combustion cycle engine according to claim 5, characterized in that: include: In the early stage of the engine starting process, the valve core (15) of the transfer valve (12) is locked by the lock pin (11), the transfer valve (12) is initially in a small opening state, the flow regulator (2) is in an unadjusted state, the slide valve (4) is pressed against the housing by the spring (6), and the steady flow window (5) is in a state of maximum flow area; As the engine operating conditions increase, the inlet pressure of the flow regulator (2) increases. After the diaphragm (10) is squeezed and ruptured by the high-pressure medium, the valve core (15) moves toward the damping chamber (14) under the action of the inlet pressure, the pressure of the damping chamber (14) and the spring force. As a result, the flow area of ​​the transfer valve (12) gradually increases, thereby controlling the flow entering the gas generator to increase steadily and rapidly in the early and middle stages of the engine starting process. When the engine operating condition climbs to a level close to the rated operating condition, the pressure drop of the throttle window (7) exceeds the design threshold, and the slide valve (4) begins to move toward the outlet side under the action of the inlet pressure, the intermediate chamber pressure and the spring force. The movement rate is positively correlated with the pressure drop of the throttle window (7), and the flow area of ​​the steady flow window (5) is therefore reduced, thereby stabilizing the fuel flow entering the gas generator at the end of the engine starting process.

9. The method according to claim 8, characterized in that Before being assembled to the engine, a separate fluid flow test of the starting control system is conducted, and the test target of a flow overshoot of no more than 5% is achieved by adjusting the apertures of the damping hole (1) and the damping pin (8).

10. The method according to claim 9, characterized in that In the fluid action test of the starting control system, the inlet and outlet pressure environment is the same as the test environment.

Images