Low pressure turbine blade cold gas active regulation system

Abstract

The application provides a low-pressure turbine blade cold air active regulation system, and belongs to the technical field of aero-engines. The system comprises a cooling bleed pipe, a cold air control valve, a control bleed pipe and a control bleed electromagnetic valve. The cooling bleed pipe is connected with a compressor and a low-pressure turbine blade. Cold air is extracted from the compressor and delivered to the low-pressure turbine blade. The cold air control valve is arranged on the cooling bleed pipe. The control bleed pipe is connected with the compressor and the cold air control valve. The control bleed electromagnetic valve is arranged on the control bleed pipe. When the engine-related working parameters meet the cold air regulation triggering conditions of the active regulation system working condition, the control bleed electromagnetic valve is opened. The control bleed electromagnetic valve leads the control bleed from the compressor and distributes it to the cold air control valve according to the on-off logic of the cold air control valve. The cold air control valve is opened or closed under the combined action of the cold air control valve, so as to realize the active regulation of the low-pressure turbine blade cold air under the working condition.

Description

Technical Field

[0001] This application belongs to the field of aero-engine technology, and specifically relates to a low-pressure turbine blade cooling active regulation system. Background Technology

[0002] With the increasing demands on performance and fuel consumption of aero engines, the existing technology has proposed variable cycle engines. These engines switch cycle modes under different flight conditions by changing the geometry or airflow path of engine components (such as compressors, turbines, and ducts). This balances the needs of high thrust at high speeds with low fuel consumption at low speeds, and economically and reliably ensures the safe operation of the engine's internal environment, which faces enormous challenges.

[0003] However, as the operating conditions of the engine become wider, the problem of the amount of cold air used by the low-pressure turbine blades gradually becomes apparent. Under a wide range of operating conditions, the amount of cold air used by the low-pressure turbine blades at high altitudes such as ground takeoff is basically the same as that at low altitudes such as subcruise. This results in excessive use of cold air at low altitudes such as subcruise, leading to a decrease in engine performance and a higher fuel consumption rate. Summary of the Invention

[0004] The purpose of this application is to provide a low-pressure turbine blade cooling gas active regulation system to solve or mitigate at least one of the problems in the prior art.

[0005] The technical solution of this application is: a low-pressure turbine blade cooling gas active regulation system, including: a cooling bleed pipe, a cooling gas control valve, a control bleed pipe and a control bleed solenoid valve;

[0006] The cooling air intake pipe connects the compressor and the low-pressure turbine blades, extracts cold air from the compressor and delivers the cold air to the low-pressure turbine blades for cooling the low-pressure turbine blades.

[0007] The cooling gas control valve is installed on the cooling gas duct and is used to control the flow rate or on / off state of the cooling gas duct. The cooling gas control valve is a gas-controlled valve.

[0008] The control air intake pipe connects the compressor and the cold air control valve, and the flow rate or on / off control of the cold air control valve is achieved by controlling the air intake.

[0009] The control bleed air solenoid valve is installed on the control bleed air pipe and is used to open or close the control bleed air pipe.

[0010] When the relevant operating parameters of the engine meet the cold air regulation trigger conditions of the active adjustment system, the control bleed air solenoid valve opens. The control bleed air solenoid valve draws control bleed air from the compressor and distributes it to the cold air control valve according to the on / off logic of the cold air control valve. Under the combined force, the cold air control valve opens or closes the cold air control valve of the cooling bleed air pipe, realizing the active regulation of the cold air of the low-pressure turbine blades under this operating condition.

[0011] In at least one embodiment of the present invention, the relevant engine operating parameter is the throttle lever angle PLA. When the condition is met, the air conditioning adjustment trigger condition of the active adjustment system is 20° < throttle lever angle PLA < 50°.

[0012] In at least one embodiment of the present invention, the controlled bleed air satisfies: the outlet bleed air pressure P of the controlled bleed air solenoid valve. 引 The ambient pressure P of the air conditioning control valve is greater than or equal to the ambient pressure of the air conditioning control valve. 阀 The pressure difference P between the valve and the valve's ability to close and maintain the closed state. 弹 The sum is:

[0013] P 引 ≥P 阀 +P 弹 .

[0014] In at least one embodiment of the present invention, the valve is capable of closing and maintaining a pressure difference P in the closed state. 弹 Depending on the model and valve characteristics of the air conditioning control valve; the outlet bleed pressure P of the control bleed solenoid valve. 引 The value is achieved by selecting a suitable compressor bleed position.

[0015] In at least one embodiment of the present invention, the process by which the control bleed air solenoid valve draws control bleed air from the compressor and distributes it to the cold air control valve according to the on / off logic of the cold air control valve includes:

[0016] Determine the total number of cooling vent pipes n0 required;

[0017] Based on the minimum gas volume W for cooling low-pressure turbine blades 总 Determine the number of air vent pipes n1 that need to be adjusted. If the number of air vent pipes n1 that need to be adjusted is an integer or approximately equal to a certain value, then install a cooling control valve on the n0-n1 cooling air vent pipes. At this time, the on / off logic of the cooling control valve is that the cooling control valve is closed when the active adjustment system is working, and open in other non-adjustment conditions.

[0018] If the number of airway tubes that need adjustment is not an integer, then...

[0019] 1) Adjust the number of airway tubes n1 that needs to be adjusted to an integer or approximately an integer;

[0020] 2) A multi-stage adjustable air conditioning control valve is used. Each time the valve is adjusted, the flow characteristics of the cooling air ducts are recalculated in the air system network model to obtain the vent flow rate w1 for a single cooling air duct. The number of cooling air ducts requiring adjustment is n2. When the air conditioning control valve 12 is adjusted to the L position, the number of cooling air ducts n2 is an integer or approximately an integer, and n2≤n0. At this time, the air conditioning control valve is installed on n2 cooling air ducts. The valve on / off logic is that when the active adjustment system is working, the air conditioning control valve is adjusted to the L position. Under other non-adjustment conditions, the air conditioning control valve is in the open state.

[0021] In at least one embodiment of the present invention, the process of determining the number n0 of the adjusted cooling air ducts is as follows:

[0022] The minimum gas flow rate for sealing the low-pressure turbine rim gas, the minimum gas flow rate for cooling the low-pressure turbine disk and components, and the minimum gas flow rate required for cooling the low-pressure turbine working blades and guide vanes under the operating conditions of the active control system were determined. The minimum gas flow rate W for cooling the low-pressure turbine blades was obtained through air system flow path design calculations. 总 The number of cooling exhaust pipes n0 that need to be adjusted is calculated based on the flow characteristics of the exhaust pipes.

[0023] In at least one embodiment of the present invention, the method for adjusting the number of air intake pipes n1 to be adjusted to an integer is as follows: by adjusting the diameter of the cooling air intake pipe in the original scheme, the number of air intake pipes n1 to be adjusted is adjusted to an integer.

[0024] The low-pressure turbine blade cooling air active adjustment system provided by this invention determines whether the relevant engine operating parameters meet the cooling air adjustment trigger conditions under a certain operating condition. When the conditions are met, the active adjustment system is activated, and the bleed air solenoid valve is controlled to distribute the control bleed air to the corresponding cooling control valve according to the on / off logic of the cooling control valve. Under the combined action of the cooling control valve, the bleed air pipe valve is opened or closed, thereby realizing the active adjustment of the amount of cooling air used by the low-pressure turbine blade under this operating condition, reducing the amount of cooling air for the blade in low-level conditions such as subcruise, and reducing fuel consumption. Attached Figure Description

[0025] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0026] Figure 1 This is a schematic diagram of the low-pressure turbine blade cooling gas active regulation system of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0028] To overcome the problem that a wide-condition variable cycle engine has an appropriate amount of cooling air for the low-pressure turbine blades under high conditions (i.e., high speed, high thrust, and high power), but excessive cooling air for the low-pressure turbine blades under low conditions (i.e., low speed, low thrust, and low power), resulting in high fuel consumption, this invention provides an active cooling air regulation system for low-pressure turbine blades. This system can automatically and actively regulate the amount of cooling air for the low-pressure turbine blades under low conditions, thereby reducing the amount of cooling air for the low-pressure turbine blades and lowering the fuel consumption rate.

[0029] like Figure 1 As shown, the low-pressure turbine blade cooling gas active regulation system 10 provided by the present invention includes: a cooling bleed pipe 11, a cooling gas control valve 12, a control bleed pipe 13, and a control bleed solenoid valve 14.

[0030] The cooling bleed pipe 11 typically consists of multiple pipes, connecting the compressor 20 and the low-pressure turbine blades 30. Cool air is extracted from the compressor 20 and delivered to the low-pressure turbine blades 30 for cooling. A cooling air control valve 12 is installed on the cooling bleed pipe 11 to control the flow rate or on / off state of the cooling bleed pipe 11. The cooling air control valve 12 is a gas-controlled valve, and the control bleed pipe 13 connects the compressor 20 and the cooling air control valve 12, controlling the flow rate or on / off state of the cooling air control valve 12 by controlling the bleed air flow. A control bleed air solenoid valve 14 is installed on the control bleed air pipe 13 to open or close the control bleed air pipe 13.

[0031] In some embodiments of the present invention, multiple cooling air ducts 50 can draw air from the same location or the same stage compression gap of the compressor 20, or from different locations or different stages compression gaps. For example, multiple cooling air ducts 11 all draw air from the gap between the third and fourth stage blades of the compressor 20.

[0032] When the relevant operating parameters of the engine meet the cold air regulation triggering conditions of the active adjustment system, the control bleed air solenoid valve 14 opens, drawing control bleed air from the compressor 20 and distributing it to the cold air control valve 12 according to the on / off logic of the cold air control valve 12. Under the combined force, the cold air control valve 12 opens or closes the cooling bleed air pipe, realizing the active regulation of the low-pressure turbine blade cold air under this operating condition.

[0033] In this invention, the air conditioning adjustment trigger condition is: the engine-related operating parameters are selected as throttle lever angle (PLA), and 20° < PLA < 50°. When the engine-related operating parameters meet the above requirements, the active adjustment system is activated; otherwise, it cannot be activated.

[0034] In this invention, to ensure the proper functioning of the air conditioning control valve 12, the outlet bleed pressure P of the bleed solenoid valve 14 is controlled according to the working principle of the air conditioning control valve 12. 引 The ambient pressure P at which the air conditioning control valve 12 is greater than or equal to the installation pressure of the air conditioning control valve is greater than or equal to the ambient pressure of the air conditioning control valve 12. 阀 The pressure difference P between the valve and the valve's ability to close and maintain the closed state. 弹 The sum is:

[0035] P 引 ≥P 阀 +P 弹

[0036] Wherein, pressure difference P 弹 It depends on the model and valve characteristics of the air conditioning control valve 12. It is based on the outlet bleed pressure P of the control bleed solenoid valve 14. 引 The value is selected to determine the appropriate compressor bleed position, generally choosing the outlet gas of a certain stage of the compressor. For example, when controlling the outlet bleed pressure P of the bleed solenoid valve 14... 引 When the value is large (i.e., higher pressure is required), the outlet gas from a later stage in the compressor can be selected. When controlling the outlet bleed pressure P of the bleed solenoid valve 14... 引 When the value is small (i.e., a smaller pressure is required), the outlet gas of the compressor stage earlier can be selected.

[0037] In this invention, based on the minimum gas volume required for sealing the low-pressure turbine rim gas, the minimum gas volume required for cooling the low-pressure turbine disk and components, and the minimum gas volume required for cooling the low-pressure turbine working blades and guide vanes under the operating conditions of the active control system, the minimum gas volume W for cooling the low-pressure turbine blades is calculated through air system flow path design (functional flow path coupling and decoupling design, etc.). 总 The total number of cooling exhaust pipes n0 required is calculated based on the exhaust pipe flow characteristics.

[0038] In addition, in order to ensure that the cooling air volume of the low-pressure turbine blades is not affected under the non-operating conditions of the active adjustment system under a wide range of operating conditions, the number of engine cooling bleed air pipes n0 cannot be changed. Therefore, the bleed air volume is adjusted by installing a cold air control valve 12 on the cold air bleed air pipe 11.

[0039] Based on the minimum gas volume W for cooling low-pressure turbine blades 总Determine the number of air ducts n1 that need adjustment. If the number of air ducts n1 is approximately an integer, then install a cooling control valve 12 on each of the n0-n1 cooling air ducts 11. The on / off logic of the cooling control valve 12 is as follows: when the active adjustment system is working, the cooling control valve 12 is always closed; otherwise, it is always open. If the number of air ducts n1 that needs adjustment is not an integer, there are two solutions: one is to adjust the diameter and number of cooling air ducts 11 (or orifice plates) in the original solution to adjust the number of air ducts n1 to an integer; the other is to use a multi-stage adjustable cooling control valve 12. Each time the valve 12 is adjusted, the flow characteristics of the cooling air duct 11 are recalculated in the air system network model to obtain the air flow rate w1 of a single cooling air duct 11. The number of cooling air ducts that need adjustment is approximately n2 = Assuming that when the air conditioning control valve 12 is adjusted to the L position, the number of cooling air intake pipes n2 is approximately an integer and n2≤n0. At this time, the air conditioning control valve 12 is installed on n2 cooling air intake pipes 11. The valve on / off logic is that when the active adjustment system is working, the air conditioning control valve 12 is adjusted to the L position. Under other non-adjustment conditions, the air conditioning control valve 12 is in the open state.

[0040] The low-pressure turbine blade cooling air active adjustment system provided by this invention determines whether the relevant engine operating parameters meet the cooling air adjustment trigger conditions under a certain operating condition. When the conditions are met, the active adjustment system is activated, and the bleed air solenoid valve is controlled to distribute the control bleed air to the corresponding cooling control valve according to the on / off logic of the cooling control valve. Under the combined action of the cooling control valve, the bleed air pipe valve is opened or closed, thereby realizing the active adjustment of the amount of cooling air used by the low-pressure turbine blade under this operating condition, reducing the amount of cooling air for the blade in low-level conditions such as subcruise, and reducing fuel consumption.

[0041] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A low-pressure turbine blade cooling gas active regulation system, characterized in that, include: Cooling air duct (11), cooling air control valve (12), control air duct (13) and control air duct solenoid valve (14). The cooling air intake pipe connects the compressor (20) and the low-pressure turbine blade (30), extracts cold air from the compressor (20) and delivers the cold air to the low-pressure turbine blade (30) for cooling the low-pressure turbine blade (30); The cooling gas control valve (12) is installed on the cooling gas pipe (11) and is used to control the flow rate or on / off state of the cooling gas pipe (11). The cooling gas control valve (12) is a gas-controlled valve. The control air intake pipe (13) connects the compressor (20) and the cold air control valve (12), and the flow or on / off control of the cold air control valve (12) is realized by controlling the air intake; The control bleed air solenoid valve (14) is installed on the control bleed air pipe (13) and is used to open or close the control bleed air pipe (13). When the relevant operating parameters of the engine meet the cold air regulation triggering conditions of the active adjustment system, the control bleed air solenoid valve (14) opens. The control bleed air solenoid valve (14) draws control bleed air from the compressor (20) and distributes it to the cold air control valve (12) according to the on / off logic of the cold air control valve (12). The cold air control valve (12) opens or closes the cold air control valve (12) of the cooling bleed air pipe under the combined force, thereby realizing the active adjustment of the cold air of the low-pressure turbine blades under this operating condition.

2. The low-pressure turbine blade cooling gas active regulation system as described in claim 1, characterized in that, The relevant engine operating parameter is the throttle lever angle PLA. When the following conditions are met, the air conditioning adjustment trigger condition of the active adjustment system is 20° < throttle lever angle PLA < 50°.

3. The low-pressure turbine blade cooling gas active regulation system as described in claim 1, characterized in that, The controlled bleed air meets the following condition: the outlet bleed air pressure P of the controlled bleed air solenoid valve (14) is... 引 The ambient pressure P of the air conditioning control valve (12) is greater than or equal to the ambient pressure P. 阀 The pressure difference P between the valve and the valve's ability to close and maintain the closed state. 弹 The sum is: P 引 ≥P 阀 +P 弹 。 4. The low-pressure turbine blade cooling gas active regulation system as described in claim 3, characterized in that, The valve can close and maintain the closed state with a pressure difference P. 弹 Depending on the model and valve characteristics of the air conditioning control valve (12); the outlet bleed pressure P of the control bleed solenoid valve (14) 引 The value is achieved by selecting a suitable compressor bleed position.

5. The low-pressure turbine blade cooling gas active regulation system as described in claim 1, characterized in that, The process by which the control bleed solenoid valve (14) draws control bleed from the compressor (20) and distributes it to the cold air control valve (12) according to the on / off logic of the cold air control valve (12) includes: Determine the total number of cooling vent pipes n0 required; Based on the minimum gas volume W for cooling low-pressure turbine blades 总 Determine the number of air intake pipes n1 that need to be adjusted. If the number of air intake pipes n1 that need to be adjusted is an integer or approximately equal to a certain value, then install a cooling control valve (12) on the n0-n1 cooling air intake pipes (11). At this time, the on / off logic of the cooling control valve (12) is that the cooling control valve (12) is closed when the active adjustment system is working, and open when the cooling control valve (12) is not in other adjustment conditions. If the number of airway tubes that need adjustment is not an integer, then... 1) Adjust the number of airway tubes n1 that needs to be adjusted to an integer or approximately an integer; 2) A multi-stage adjustable air conditioning control valve (12) is used. For each stage of adjustment, the flow characteristics of the cooling air intake pipe (11) are recalculated in the air system network model to obtain the air intake flow rate w1 of a single cooling air intake pipe (11). The number of cooling air intake pipes requiring adjustment is n2 = When the valve of the air conditioning control valve 12 is adjusted to the L position, the number of cooling air ducts n2 is an integer or approximately an integer, and n2≤n0. At this time, the air conditioning control valve (12) is installed on the n2 cooling air ducts (11). The valve on / off logic is that when the active regulation system is working, the valve of the air conditioning control valve (12) is adjusted to the L position. Under other non-regulation conditions, the air conditioning control valve (12) is in the open state.

6. The low-pressure turbine blade cooling gas active regulation system as described in claim 5, characterized in that, The process of determining the number of cooling vent pipes n0 to be adjusted is as follows: The minimum gas flow rate for sealing the low-pressure turbine rim gas, the minimum gas flow rate for cooling the low-pressure turbine disk and components, and the minimum gas flow rate required for cooling the low-pressure turbine working blades and guide vanes under the operating conditions of the active control system were determined. The minimum gas flow rate W for cooling the low-pressure turbine blades was obtained through air system flow path design calculations. 总 The number of cooling exhaust pipes n0 that need to be adjusted is calculated based on the flow characteristics of the exhaust pipes.

7. The low-pressure turbine blade cooling gas active regulation system as described in claim 5, characterized in that, The method to adjust the number of air intake pipes n1 to an integer is as follows: by adjusting the diameter of the cooling air intake pipe (11) in the original scheme, the number of air intake pipes n1 to be adjusted is adjusted to an integer.

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