Turbofan engine and bleed air cooling device

Abstract

A turbofan engine and bleed air cooling device are used to reduce the temperature of bleed air to improve the cooling effect of bleed air. The bleed air cooling device comprises an evaporator and a condenser; the evaporator extends circumferentially to fit the inner wall surface of the outer peripheral wall of the bleed air collection cavity, the evaporator comprises a vapor cavity, a capillary core and a liquid storage cavity, the liquid storage cavity is located on the outer peripheral side, the capillary core is wrapped on the inner peripheral side of the liquid storage cavity, and the vapor cavity is wrapped on the inner peripheral side of the capillary liquid storage core; the condenser is arranged on the outer peripheral side of the bleed air collection cavity, the vapor cavity is communicated with the condenser to transport gaseous working medium to the condenser, and the condenser is communicated with the liquid storage cavity to transport liquid working medium to the liquid storage cavity.

Description

Technical Field

[0001] This invention relates to bleed air precooling technology, specifically to a turbofan engine and a bleed air cooling device. Background Technology

[0002] Aero-engine turbine components operate in extremely harsh, high-temperature environments. Currently, the conventional cooling method involves cooling the turbine components with bleed air from the compressor's final and intermediate stages. However, as the pressure ratio of aero-engines continues to increase, the temperatures of the compressor's intermediate and final stages are rising, leading to a continuous increase in bleed air temperature and a deterioration in the cooling effect on turbine components. Therefore, improving the cooling capacity of the bleed air is becoming increasingly important.

[0003] Currently, bleed air precooling technology is used to further cool bleed air, thereby improving its cooling capacity. Conventional bleed air precooling methods involve using a partition wall heat exchanger, with external air or aviation kerosene as the cold source and bleed air as the heat source, cooling the bleed air through heat exchange via the pipe wall flow. However, this method has low cooling efficiency, large equipment size, and numerous complex spiral and fin structures leading to significant pressure and flow losses, thus limiting its application. Summary of the Invention

[0004] The purpose of this invention is to provide a turbofan engine and an bleed air cooling device for reducing bleed air temperature to improve bleed air cooling effect.

[0005] In a first aspect, the present invention provides a gas-drawing cooling device. According to an embodiment of the present invention, the gas-drawing cooling device includes an evaporator and a condenser; the evaporator extends circumferentially to fit the inner wall surface of the outer peripheral wall of the gas-drawing and collecting cavity, the evaporator includes a vapor chamber, a capillary wick, and a liquid storage chamber, the liquid storage chamber is located on the outer peripheral side, the capillary wick covers the inner peripheral side of the liquid storage chamber, and the vapor chamber covers the inner peripheral side of the capillary liquid storage wick; the condenser is disposed on the outer peripheral side of the gas-drawing and collecting cavity, the vapor chamber is connected to the condenser to deliver a gaseous working medium to the condenser, and the condenser is connected to the liquid storage chamber to deliver a liquid working medium to the liquid storage chamber.

[0006] In one or more embodiments, the vapor chamber is provided with a first fin array, the first fin array including a plurality of first fin rows arranged axially, the plurality of first fins in each first fin row having circumferential spacing and being evenly distributed circumferentially, and forming a plurality of first fin columns evenly distributed circumferentially, the plurality of first fins in each first fin column having axial spacing and being evenly distributed axially, and each first fin protruding from the inner peripheral wall of the vapor chamber toward the inner peripheral side.

[0007] In one or more embodiments, each first fin extends inward along an arc to bulge toward the outflow direction of the air intake and collection cavity.

[0008] In one or more embodiments, the radial height of the evaporator is less than or equal to one-tenth of the circumferential length of the evaporator.

[0009] In one or more embodiments, the radial height of each first fin is less than or equal to the radial height of the evaporator.

[0010] In one or more embodiments, the condenser may be provided by a thermoacoustic heat exchanger, the condenser including a grid and condenser tubes located within the grid, the grid including a plurality of second fins for thermoacoustic gas oscillating in the grid to thermoacoustically cool the condenser tubes.

[0011] In one or more embodiments, the condenser further includes a fan-shaped frame extending circumferentially, the grille being disposed on the fan-shaped frame, each of the second fins extending circumferentially and connected to the circumferential end wall of the fan-shaped frame, the plurality of second fins having radial spacing and being radially evenly distributed.

[0012] In one or more embodiments, the vapor chamber is connected to the condenser via a double-layered vacuum pipe, and the condenser is connected to the liquid storage chamber via a double-layered vacuum pipe.

[0013] Secondly, the present invention provides a turbofan engine, wherein, according to an embodiment of the present invention, the turbofan engine includes the above-described bleed air cooling device.

[0014] The embodiments of the present invention possess at least one of the following beneficial effects:

[0015] The evaporator extends circumferentially to fit the outer wall of the induced draft gas collection chamber, reducing its impact on the induced draft gas flow and minimizing pressure loss. The evaporator utilizes phase change heat absorption to enhance induced draft gas cooling. The capillary wick is located on the inner circumference of the liquid storage chamber and covers it, increasing the evaporation surface area of ​​the capillary wick and improving cooling of the induced draft gas. The vapor chamber is located on the inner circumference of the capillary wick and covers it, increasing the heat exchange area with the induced draft gas in the induced draft gas collection chamber and further enhancing cooling of the induced draft gas. Attached Figure Description

[0016] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, wherein:

[0017] Figure 1 This is a schematic diagram of the use of the induced draft cooling device;

[0018] Figure 2 This is a right view of the induced draft cooling device;

[0019] Figure 3 This is a front view of the induced draft cooling device;

[0020] Figure 4 for Figure 2 Sectional view at CC;

[0021] Figure 5 This is a magnified view of a portion of the evaporator;

[0022] Figure 6 This is a perspective view of the steam chamber;

[0023] Figure 7 This is a magnified view of a portion of the first fin.

[0024] Figure label:

[0025] 1-Gas collection chamber;

[0026] 2-Evaporator;

[0027] 3-The outer peripheral wall of the air intake and collection chamber;

[0028] 4- Intermediate stage air intake port of high-pressure compressor;

[0029] 5-External pipeline outlet;

[0030] 6-Vacuum chamber;

[0031] 7-Capillary core;

[0032] 8-Liquid reservoir;

[0033] 9-Condenser;

[0034] 10 - First fin array;

[0035] 11-First fin;

[0036] 12 - First fin row;

[0037] 13-Grate;

[0038] 14-Condenser;

[0039] 15 - Second fin;

[0040] 16-Sector-shaped frame;

[0041] 17-Double-layer vacuum tube. Detailed Implementation

[0042] The present invention will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.

[0043] It should be noted that these and other accompanying drawings are merely examples and are not drawn to scale, and should not be construed as limiting the scope of protection of the present invention.

[0044] The terms “first”, “second”, etc., are used interchangeably to distinguish one feature from another and are not intended to indicate that each feature must be located in the position shown in the figure in each embodiment.

[0045] like Figure 1 As shown, the turbofan engine includes a bleed air cooling device. This device is used to cool the bleed air within the bleed air collection chamber 1. The bleed air collection chamber 1 can be a compressor bleed air collection chamber or a high-pressure turbine bleed air collection chamber. Figure 1 In the embodiment shown, the bleed air collection chamber 1 is the compressor bleed air collection chamber. Bleed air flows into the bleed air collection chamber 1 through the intermediate stage bleed air hole 4 of the high-pressure compressor, flows out of the bleed air collection chamber 1 through the external pipeline outlet 5, and flows to the turbine casing collection chamber for cooling the high-temperature components of the turbine.

[0046] like Figures 2 to 4 As shown, the induced draft cooling device includes an evaporator 2. The evaporator 2's induced draft cooling effect, based on phase change heat absorption, is superior to the induced draft cooling effect of the indirect heat exchanger described in the background art. The evaporator 2 extends circumferentially to fit the inner wall surface of the outer peripheral wall 3 of the induced draft collecting cavity 1. The evaporator 2 is disposed within the induced draft collecting cavity 1, and its circumferential extension creates an arc shape. This allows the outer peripheral wall of the evaporator 2 to fit snugly against the arc-shaped outer peripheral wall 3 of the induced draft collecting cavity 1, reducing the impact on the induced draft flow within the cavity and minimizing pressure loss. The evaporator 2 can be fixed to the outer peripheral wall 3 of the induced draft collecting cavity 1 via a slot and a snap-fit ​​connection.

[0047] like Figure 5As shown, the evaporator 2 includes a vapor chamber 6, a capillary wick 7, and a liquid storage chamber 8. The liquid storage chamber 8 contains the liquid working medium, and the vapor chamber 6 contains the gaseous working medium. The working medium can be thermally conductive A (DOTHERM-A), with an operating temperature range of 200–550°C. In the evaporator 2, the liquid storage chamber 8 is located on the outer periphery and extends circumferentially. In the evaporator 2, the capillary wick 7 is located on the inner periphery of the liquid storage chamber 8 and covers it, extending circumferentially. In the evaporator 2, the vapor chamber 6 is located on the inner periphery of the capillary wick 7 and covers it, extending circumferentially. The capillary wick 7 can be made of a porous material, such as metal mesh or sintered metal powder. The capillary wick 7, through its internal capillary structure, transports the liquid working medium from the storage chamber 8 to its surface. During the process of absorbing heat from the induced draft gas and thus cooling it, the liquid working medium on the surface of the capillary wick 7 evaporates into a gaseous working medium, which enters the vapor chamber 6 and flows from the vapor chamber 6 to the condenser 9 (described later), where it condenses back into a liquid working medium. The condensed liquid working medium, under the capillary force of the capillary wick 7, flows back to the storage chamber 8 to complete the cycle. The capillary wick 7 is located on the inner circumference of the storage chamber 8 and covers it, increasing the evaporation surface area of ​​the capillary wick 7 and improving the cooling effect on the induced draft gas. The vapor chamber 6 is located on the inner circumference of the capillary wick 7 and covers it, increasing the heat exchange area with the induced draft gas in the induced draft gas collection chamber 1 and improving the cooling effect on the induced draft gas. The porous structure of the capillary wick 7 provides a large evaporation interface for the liquid working medium, increasing the evaporation surface area of ​​the capillary wick 7 and improving the cooling effect on the induced draft gas. The capillary wick 7 also effectively prevents the gaseous working medium in the vapor chamber 6 from directly entering the liquid storage chamber 8, preventing the vapor from condensing into the liquid working medium in the liquid storage chamber 8, thereby maintaining the stability of the liquid working medium in the liquid storage chamber 8.

[0048] like Figures 2 to 4 As shown, the induced draft cooling device also includes a condenser 9. Further combined with... Figure 1 The condenser 9 is located on the outer periphery of the induced draft gas collecting chamber 1. This location avoids affecting the induced draft gas flow within the chamber and causing pressure loss, and also prevents the condenser 9 from releasing heat, which could lead to a rise in the temperature of the induced draft gas within the chamber and degrade the cooling effect. Figure 5 As shown, the vapor chamber 6 is connected to the condenser 9 to supply the gaseous working medium to the condenser 9. The gaseous working medium in the vapor chamber 6 flows to the condenser 9, and the condenser 9 condenses the gaseous working medium into a liquid working medium. The condenser 9 is connected to the liquid storage chamber 8 to supply the liquid working medium to the liquid storage chamber 8. The condensed liquid working medium flows back to the liquid storage chamber 8 under the capillary force of the capillary wick 7.

[0049] like Figures 2 to 5As shown, the radial height of the evaporator 2 can be less than or equal to one-tenth of the circumferential length of the evaporator 2. This limits the maximum ratio of the radial height of the evaporator 2 to the circumferential length of the evaporator 2, limits the radial height of the evaporator 2 protruding from the inner wall of the outer peripheral wall 3 of the air intake chamber 1 to the inner peripheral side, reduces the influence of the evaporator 2 on the air intake flow in the air intake chamber 1, and reduces the pressure loss of the air intake.

[0050] like Figure 6 and Figure 7 As shown, the steam chamber 6 may be provided with a first fin array 10. The first fin array 10 includes a plurality of first fins 11, each first fin 11 protruding from the inner peripheral wall of the steam chamber 6 toward the inner peripheral side. The first fins 11 in the first fin array 10 form a plurality of first fin rows 12, in Figure 6 and Figure 7 In the diagram, multiple first fins 11 in a first fin row 12 are connected by dashed lines for clearer illustration. The multiple first fins 11 in each first fin row 12 have circumferential spacing and are evenly distributed circumferentially. Any two circumferentially adjacent first fins 11 in each first fin row 12 have the same circumferential spacing. The multiple first fin rows 12 are arranged axially. As described later, the multiple first fins 11 in each first fin array 13 have axial spacing and are evenly distributed axially. Furthermore, the first fins 11 in the first fin array 10 also form multiple first fin arrays 13. Figure 6 and Figure 7 In the diagram, multiple first fins 11 in a first fin row 13 are connected by dashed lines for clearer illustration. The multiple first fins 11 in each first fin row 13 are axially spaced and evenly distributed along the axial direction. Any two axially adjacent first fins 11 in each first fin row 13 have the same axial spacing. The multiple first fin rows 13 are evenly distributed circumferentially. As mentioned earlier, the multiple first fins 11 in each first fin row 12 are circumferentially spaced and evenly distributed circumferentially. This causes the first fin array 10 to form multiple circumferentially extending flow channels and multiple axially extending flow channels. The induced air in the induced air collection chamber 1 flows within the flow channels and exchanges heat with the first fins 11, increasing the heat exchange area between the evaporator 2 and the induced air in the induced air collection chamber 1, and increasing the turbulence of the induced air flow within the induced air collection chamber 1, thereby enhancing the heat exchange intensity with the induced air and improving the cooling effect on the induced air.

[0051] like Figure 7As shown, each first fin 11 can protrude along the arc towards the inner periphery to bulge in the outflow direction of the air intake and collection cavity 1. The outflow direction is the direction of air intake flow in the air intake and collection cavity 1, and the inflow direction described later is the opposite direction of air intake flow in the air intake and collection cavity 1. This makes the surface of the first fin 11 facing the inflow of air intake concave inward and the surface of the first fin 11 facing the outflow of air intake concave outward, further increasing the heat exchange area between the evaporator 2 and the air intake in the air intake and collection cavity 1, and increasing the turbulence of the air intake flow in the air intake and collection cavity 1.

[0052] like Figure 7 As shown, the radial height of each first fin 11 can be less than or equal to the radial height of the evaporator 2. This limits the maximum radial height of the first fin 11, limits the radial height of the first fin 11 protruding from the inner peripheral wall of the vapor chamber 6 to the inner peripheral side, limits the maximum influence of the first fin 11 on the air intake flow in the air intake chamber 1, and avoids excessive pressure loss of the air intake.

[0053] like Figures 1 to 4 As shown, the condenser 9 can be provided by a thermoacoustic heat exchanger. The condenser 9 can be the refrigeration unit of the thermoacoustic heat exchanger. The condenser 9 may include a grille 13 and condenser tubes 14. The condenser tubes 14 are located within the grille 13, which includes multiple second fins 15. The heat released by the condenser tubes 14 causes the thermoacoustic gas to acoustically self-excite and oscillate within the grille 13, achieving thermoacoustic refrigeration. Heat absorbed from the condenser tubes 14 causes the gaseous working medium within the condenser tubes 14 to condense into a liquid working medium. The thermoacoustic gas can be a high-pressure inert gas. The heat absorbed from the condenser tubes 14 can be further used in the heating unit of the thermoacoustic heat exchanger, where the heat grade is improved by a thermoacoustic heat pump for further utilization.

[0054] like Figures 1 to 4 As shown, the condenser 9 may also include a fan-shaped frame 16. The fan-shaped frame 16 extends circumferentially, thus forming an arc shape, which makes the condenser 9 suitable for arrangement in the space on the outer periphery of the air intake and collection chamber 1. A grille 13 is disposed on the fan-shaped frame 16, located within the hollow channel of the fan-shaped frame 16. The condenser tube 14 is also located within the hollow channel of the fan-shaped frame 16 and is covered by the grille 13. Each second fin 15 extends circumferentially, and the two circumferential ends of each second fin 15 are respectively connected to the two circumferential end walls of the fan-shaped frame 16, which makes the grille 13 arc-shaped, suitable for arrangement in the space on the outer periphery of the air intake and collection chamber 1. The plurality of second fins 15 have radial spacing and are evenly distributed radially, and any two radially adjacent second fins 15 have the same radial spacing.

[0055] like Figures 1 to 5 As shown, the vapor chamber 6 can be connected to the condenser 9 through the double-layer vacuum pipe 17, and the condenser 9 can be connected to the liquid storage chamber 8 through the double-layer vacuum pipe 17. The double-layer vacuum pipe 17 includes an inner wall and an outer wall, and there is a vacuum layer between the inner wall and the outer wall, which provides heat insulation and reduces weight.

[0056] Although the present invention has been disclosed above with reference to embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention.

Claims

1. A induced draft cooling device, characterized in that... include: An evaporator extends circumferentially to fit the inner wall surface of the outer peripheral wall of the gas collection chamber. The evaporator includes a vapor chamber, a capillary wick, and a liquid storage chamber. The liquid storage chamber is located on the outer peripheral side, the capillary wick covers the inner peripheral side of the liquid storage chamber, and the vapor chamber covers the inner peripheral side of the capillary liquid storage wick. as well as A condenser is provided on the outer periphery of the gas collection chamber. The vapor chamber is connected to the condenser to supply a gaseous working medium to the condenser, and the condenser is connected to the liquid storage chamber to supply a liquid working medium to the liquid storage chamber.

2. The air-cooling device according to claim 1, characterized in that: The steam chamber is provided with a first fin array, which includes a plurality of first fin rows arranged along the axial direction. The plurality of first fins in each first fin row are circumferentially spaced and evenly distributed along the circumferential direction, forming a plurality of first fin columns evenly distributed along the circumferential direction. The plurality of first fins in each first fin column are axially spaced and evenly distributed along the axial direction. Each first fin protrudes from the inner peripheral wall of the steam chamber toward the inner peripheral side.

3. The air-cooling device according to claim 2, characterized in that: Each of the first fins extends inward along an arc to bulge in the direction of the outflow of the air intake and collection cavity.

4. The air-cooling device according to claim 1, characterized in that: The radial height of the evaporator is less than or equal to one-tenth of the circumferential length of the evaporator.

5. The air-cooling device according to claim 2, characterized in that: The radial height of the evaporator is less than or equal to one-tenth of the circumferential length of the evaporator; The radial height of each first fin is less than or equal to the radial height of the evaporator.

6. The air-cooling device according to claim 1, characterized in that: The condenser may be provided by a thermoacoustic heat exchanger, the condenser including a grid and condenser tubes, the condenser tubes being located within the grid, the grid including a plurality of second fins for thermoacoustic gas oscillating in the grid to thermoacoustically cool the condenser tubes.

7. The air-cooling device according to claim 6, characterized in that: The condenser also includes a fan-shaped frame that extends circumferentially, a grille disposed on the fan-shaped frame, each of the second fins extending circumferentially and connected to the circumferential end wall of the fan-shaped frame, and the plurality of second fins having radial spacing and being evenly distributed radially.

8. The air-cooling device according to claim 1, characterized in that: The vapor chamber is connected to the condenser via a double-layered vacuum pipe, and the condenser is connected to the liquid storage chamber via a double-layered vacuum pipe.

9. A turbofan engine, characterized in that... Includes the air-cooling device as described in any one of claims 1 to 8.

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