Air cycle machine

Abstract

The utility model provides an air cycle machine which comprises a turbine, the turbine comprises a turbine cover, a spiral pipeline is wound on the outer wall face of the turbine cover, an inner hole of the spiral pipeline is used for being filled with fluid for heating the turbine cover, and therefore the technical problem that in the prior art, a turbine cover of a turbine is heated unevenly can be solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of air circulation machines, and particularly relates to an air circulation machine. Background Art

[0002] In an air circulation machine, the air cooled by primary heat exchange enters the compressor from C1 (compressor inlet), and is pressurized and heated by the work done by the impeller; the high-temperature and high-pressure gas is discharged from C2 (compressor outlet) and after being cooled by intermediate heat exchange, enters the turbine through T1 (turbine inlet) to complete expansion cooling and output mechanical work, and the cooling air is discharged from T2 (turbine outlet) to realize the air circulation refrigeration function. The air circulation machine system is as Figure 1 shown. The air flow temperature at the turbine outlet T2 can reach as low as -40°C at the lowest, and it is necessary to consider the possible icing situation at the turbine outlet and the drainage problem after deicing. In the past, the measures for preventing ice at the turbine outlet were mainly to form an anti-icing cavity on the outer wall surface of the turbine wheel cover, introduce high-temperature gas into the cavity for heat exchange to achieve the anti-icing effect. However, the flow of the high-temperature gas in the cavity is not uniform, and there may be a low-temperature area in a part of the turbine wheel cover, resulting in icing in some areas inside the turbine wheel cover. Due to the uneven temperature of the turbine wheel cover, it will also cause uneven pressure when the gas flows inside the turbine wheel cover, resulting in vibration.

[0003] How to heat the turbine wheel cover more evenly is a technical problem that needs to be solved urgently at present. Summary of the Utility Model

[0004] Therefore, the utility model provides an air circulation machine, which can solve the technical problem of uneven heating of the wheel cover of the turbine in the prior art.

[0005] The utility model provides an air circulation machine, including a turbine, the turbine includes a turbine cover, and a spiral pipeline is wound around the outer wall surface of the turbine cover, and the inner hole of the spiral pipeline is used for filling a fluid for heating the turbine cover.

[0006] In some embodiments, the spiral pipeline includes a first section of pipe and a second section of pipe. The end of the first section of pipe is communicated with the head of the second section of pipe and is located at the first end of the turbine cover, and the head of the first section of pipe and the end of the second section of pipe are both located at the second end of the turbine cover; the flow direction of the fluid in the first section of pipe is opposite to the flow direction in the second section of pipe.

[0007] In some embodiments, the spiral pipeline is in surface contact with the outer wall surface of the turbine cover.

[0008] In some embodiments, each loop of the first section of pipe wound around the turbine cover is arranged at intervals with each loop of the second section of pipe wound around the turbine cover.

[0009] In some embodiments, the air circulation machine further includes a compressor volute, and an inlet of the spiral duct communicates with an outlet of the compressor volute through an inlet pipe.

[0010] In some embodiments, the air circulation machine further includes a turbine volute, and an outlet of the spiral duct communicates with an inner cavity of the turbine volute through an outlet pipe.

[0011] In some embodiments, the turbine cover includes a turbine shroud and a wind guiding section connected to an outlet end of the turbine shroud. One end of the wind guiding section connected to the turbine shroud is an air inlet end, and the other end is an air outlet end; from the air inlet end to the air outlet end, the wall thickness of the wind guiding section gradually becomes thinner.

[0012] In some embodiments, the spiral duct is press-fitted around the wind guiding section.

[0013] In some embodiments, from the air inlet end to the air outlet end, the flow area of the spiral duct gradually becomes larger.

[0014] In some embodiments, an inner diameter of the spiral duct is d1, and an inner diameter of the wind guiding section is d2, and 0.1 ≤ d1 / d2 ≤ 0.2.

[0015] By surrounding the outer wall surface of the turbine cover with a spiral duct and filling a high-temperature fluid into the spiral duct, the high-temperature fluid heats the turbine cover after conducting heat through the spiral pipe. The heating fluid flows along the spiral duct, and the spiral duct is arranged around the outer wall surface of the turbine cover. In this way, the high-temperature fluid can flow through most of the surface of the turbine cover, realizing more uniform heating of the turbine cover, avoiding the phenomenon that the temperature of some areas of the turbine cover is low, resulting in local icing inside the turbine cover; at the same time, it also avoids the phenomenon of poor gas flow and vibration caused by uneven gas pressure when the gas flows inside the turbine cover due to uneven temperature. Effectively improves the anti-icing performance of the turbine cover, solves the ice blockage problem of the air circulation machine, and improves the operating temperature performance and reliability of the air circulation machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. The drawings in the following description are only exemplary, and for those of ordinary skill in the art, without creative efforts, other implementation drawings can be obtained according to the provided drawings.

[0017] Figure 1 is a schematic structural diagram of the air circulation machine according to an embodiment of the present invention;

[0018] Figure 2 is a cross-sectional view of the air circulation machine according to an embodiment of the present invention;

[0019] Figure 3 is a schematic diagram of the spiral pipe structure of the embodiment of the present utility model;

[0020] Figure 4 is a radial sectional view of the spiral pipe of the embodiment of the present utility model;

[0021] Figure 5 is a schematic diagram of the turbine cover structure of the embodiment of the present utility model;

[0022] The reference signs are as follows:

[0023] 1, turbine cover; 101, turbine shroud; 102, air guide section; 1021, first end; 1022, second end; 2, spiral pipe; 201, first section pipe; 202, second section pipe; 3, compressor volute; 301, compressor outlet; 4, turbine volute; 501, anti-icing air inlet hole; 502, anti-icing bleed air inlet; 503, anti-icing bleed air outlet; 504, anti-icing bleed air exhaust hole; 505, anti-icing bleed air pipe; 601, inlet pipe; 602, outlet pipe. Detailed implementation manners

[0024] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way constitutes a limitation to the present utility model and its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0025] In the description of the present utility model, it should be understood that the orientation terms such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom", etc. usually indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description. Without contrary description, these orientation terms do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, so they cannot be understood as limiting the protection scope of the present utility model; the orientation terms "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0026] For ease of description, spatial relative terms such as "above", "over", "on the upper surface", "upper" etc. can be used here to describe the spatial positional relationship of a device or feature shown in the figure with other devices or features. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figure for the device. For example, if the device in the figure is inverted, a device described as "above or over other devices or structures" will then be positioned "below or under other devices or structures". Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations are made for the spatial relative descriptions used here.

[0027] In addition, it should be noted that the use of terms such as "first", "second" etc. to define components is only for the convenience of differentiating the corresponding components. Without additional statements, the above terms have no special meanings, and thus should not be construed as limiting the protection scope of the present utility model.

[0028] In an air circulation machine, there is still a certain amount of water vapor in the air that enters the turbine after high-pressure water removal. During the expansion and cooling process, the temperature drops below zero degree Celsius, even below -40 °C, and part of the water vapor will sublime into ice particles. Due to the rotation of the air flow at the turbine outlet, the ice particles in the air flow accumulate on the wall surface at the turbine outlet due to inertia and block the turbine outlet after a period of time. In order to avoid the blockage of the turbine outlet by ice particles, the following technical solutions are disclosed in this application.

[0029] An air circulation machine provided by the present utility model, as Figures 1-5 shown, includes a turbine. The turbine includes a turbine cover 1, and a spiral pipe 2 is wound around the outer wall surface of the turbine cover 1. The inner hole of the spiral pipe 2 is used to fill with a fluid for heating the turbine cover 1.

[0030] By surrounding the outer wall surface of the turbine cover 1 with a spiral pipe 2, the spiral pipe 2 extends from the end of the outlet end of the turbine cover 1 to the position of the turbine cover 1 corresponding to the blades of the turbine. In the radial direction of the turbine, the spiral pipe 2 covers part of the blades of the turbine. Thus, a high-temperature fluid is filled in the spiral pipe 2, and the high-temperature fluid heats the turbine cover 1 after conducting heat through the spiral pipe. The heating fluid flows along the spiral pipe 2, and the spiral pipe 2 is arranged around the outer wall surface of the turbine cover 1. In this way, the high-temperature fluid can flow through most of the surface of the turbine cover 1, realizing more uniform heating of the turbine cover 1, avoiding low temperature in some areas of the turbine cover 1, resulting in local icing inside the turbine cover 1. At the same time, it also avoids the problems of poor gas flow and vibration caused by uneven pressure during gas flow inside the turbine cover 1 due to uneven temperature. Effectively improves the anti-icing performance of the turbine cover 1, solves the ice blockage problem of the air circulation machine, and improves the operating temperature performance and reliability of the air circulation machine.

[0031] Furthermore, the spiral pipe 2 is detachably arranged on the turbine cover 1. The detachable arrangement of the spiral pipe 2 on the outer wall surface of the turbine cover 1 facilitates the replacement and maintenance of the spiral pipe 2.

[0032] Preferably, as Figure 3 and Figure 4 shown, the spiral pipe 2 includes a first section pipe 201 and a second section pipe 202. The end of the first section pipe 201 is communicated with the head end of the second section pipe 202 and is located at the first end 1021 of the turbine cover 1. The head end of the first section pipe 201 and the end of the second section pipe 202 are both located at the second end 1022 of the turbine cover 1. The flow direction of the fluid in the first section pipe 201 is opposite to the flow direction in the second section pipe 202.

[0033] When the high-temperature fluid for heating enters the spiral pipe 2 from the head end of the first section pipe 201, the temperature of the fluid will gradually increase. When the fluid flows out from the end of the second section pipe 202, the temperature reaches the highest. This makes the overall middle temperature of the spiral pipe 2 higher than the head end of the first section pipe 201 and lower than the end of the second section pipe 202. By connecting the end of the first section pipe 201 and the head end of the second section pipe 202 and arranging them at the first end 1021 of the turbine cover 1, the temperature of the fluid heating the first end 1021 of the turbine cover 1 is relatively moderate. The fluid heating the second end 1022 of the turbine cover 1 includes the lower-temperature fluid near the head end of the first section pipe 201 and the higher-temperature fluid near the end of the second section pipe 202. Thus, the overall heating of the turbine cover 1 is more uniform.

[0034] The first end 1021 of the turbine cover 1 can be the end far from the turbine, and the other corresponding end is the second end 1022.

[0035] Preferably, the spiral pipe 2 is in surface contact with the outer wall surface of the turbine cover 1.

[0036] The first-stage pipe 201 and the second-stage pipe 202 are in contact with the outer wall surface of the turbine cover 1, which is beneficial to improving the heat exchange efficiency between the spiral pipe and the turbine cover.

[0037] Preferably, as Figure 4 shown, each turn of the pipe formed by the first-stage pipe 201 surrounding the turbine cover 1 is arranged at intervals with each turn of the pipe formed by the second-stage pipe 202 surrounding the turbine cover 1.

[0038] Each turn of the pipe formed by the first-stage pipe 201 surrounding the turbine cover 1 is arranged at intervals with each turn of the pipe formed by the second-stage pipe 202 surrounding the turbine cover 1, so that the fluids at different temperatures in the two pipes can alternately heat the turbine cover 1, further improving the uniformity of heating of the turbine cover 1.

[0039] Preferably, as Figure 2 shown, the air circulation machine further includes a compressor volute 3, and the inlet of the spiral pipe 2 is communicated with the outlet of the compressor volute 3 through an inlet pipe 601.

[0040] A part of the high-temperature gas flowing out of the outlet of the compressor volute 3 enters the spiral pipe 2 through the inlet pipe 601 to heat the turbine. There is no need for an external heat source, and only a part of the high-temperature gas needs to be introduced from the existing compressor volute 3, which is beneficial to simplifying the overall size of the air circulation machine. Without an additional heat source, the energy consumption can be reduced.

[0041] Preferably, as Figure 2 shown, the air circulation machine further includes a turbine volute 4, and the outlet of the spiral pipe 2 is communicated with the inner cavity of the turbine volute 4 through an outlet pipe 602.

[0042] The gas after heating the turbine cover 1 enters the turbine volute 4 to participate in expansion work, realizing the recovery and reuse of the heated air flow, which is beneficial to reducing energy loss.

[0043] Preferably, as Figure 2 and Figure 5 shown, the turbine cover 1 includes a turbine shroud 101 and a wind guiding section 102 connected to the outlet end of the turbine shroud 101. One end of the wind guiding section 102 connected to the turbine shroud 101 is the air inlet end, and the other end is the air outlet end; from the air inlet end to the air outlet end, the wall thickness of the wind guiding section 102 gradually becomes thinner.

[0044] When there is no device for heating the turbine cover 1, from the air inlet end to the air outlet end, the thickness of the ice formed in the air guiding section 102 gradually increases. From the air inlet end to the air outlet end, by gradually thinning the wall thickness of the air guiding section 102, it is beneficial to improve the heating efficiency near the air outlet end, and further beneficial to improve the temperature uniformity in the axial direction of the air guiding section 102.

[0045] Preferably, the spiral pipe 2 is press-fitted around the air guiding section 102.

[0046] By press-fitting the spiral pipe 2 around the air guiding section 102, the spiral pipe has a binding effect on the air guiding section 102, improving the ability of the air guiding section 102 to resist internal pressure. On the one hand, it can make the wall thickness of the air guiding section 102 thinner, improving the heat exchange efficiency; on the other hand, the heat exchange efficiency between the spiral pipe 2 and the air guiding section 102 is higher.

[0047] Furthermore, the spiral pipe 2 is made of copper or aluminum. Copper and aluminum have high thermal conductivity and certain ductility, and can be more closely wound around the air guiding section 102, absorbing the vibration of the gas flow in the air guiding section 102 and improving the stability of the air circulation machine.

[0048] Preferably, from the air inlet end to the air outlet end, the flow area of the spiral pipe 2 gradually increases.

[0049] From the air inlet end to the air outlet end, the flow area of the spiral pipe 2 gradually increases; this makes the flow velocity of the heating fluid gradually slow down from the air inlet end to the air outlet end, enabling the fluid to exchange heat with the turbine cover 1 more fully; considering the heat loss of the fluid (the heat not used for heating the turbine cover 1), the larger the flow area, the larger the volume of the fluid in the pipe per unit length, and the larger the volume of the fluid, the more heat. After removing the heat loss, the remaining heat is still relatively large, which can fully heat the turbine cover 1. In this way, the temperature uniformity in the axial direction of the air guiding section 102 is further improved.

[0050] The air circulation machine further includes a temperature control housing that surrounds the outer peripheral side of the turbine cover 1. A ring-shaped space is formed between the temperature control housing and the turbine cover 1; after the ice in the turbine cover 1 thaws, the water flows out from the air guiding section 102 along with the air flow and enters the ring-shaped space, and then flows out from the ring-shaped space.

[0051] Preferably, the inner diameter of the spiral pipe 2 is d1, and the inner diameter of the air guiding section 102 is d2, and 0.1 ≤ d1 / d2 ≤ 0.2.

[0052] The anti-icing pipe diameter d1 (mm) needs to be controlled within a certain range. If the diameter d1 is too large, although the air extraction volume is large and the anti-icing effect can be ensured, the energy loss will also increase. If the diameter is too small, the flow resistance is large, the air extraction volume is small, and the heat exchange capacity is insufficient, resulting in a poor anti-icing effect. The outlet diameter of the turbine cover is d2, and the anti-icing effect is good within the range of 0.1 ≤ d1 / d2 ≤ 0.2. Preferably, d1 / d2 = 0.15.

[0053] The high-temperature and high-pressure gas discharged from the compressor outlet 301 can, under the action of pressure, enter the inlet pipe 601 along the anti-icing air intake hole 501 on the compressor volute 3 through the anti-icing air extraction pipe 505. The high-temperature and high-pressure extracted air will pass through the anti-icing air extraction inlet 502 on the temperature control housing along the inlet pipe 601, and then enter the spiral pipe 2 through the inlet pipe 601. The high-temperature air flow will flow annularly along the spiral pipe 2, transfer heat to the turbine cover 1, and under the guiding action of the spiral pipe 2, the heat is evenly exchanged with the turbine cover 1 to prevent the turbine cover 1 from having a low-temperature area and causing anti-icing failure. The gas that has fully exchanged heat with the turbine cover 1 will flow through the outlet pipe 602 to the anti-icing air extraction outlet 503 on the temperature control housing. Finally, the gas is discharged into the turbine volute 4 through the anti-icing air extraction exhaust hole 504 to participate in expansion work, realizing the recycling of the anti-icing air flow and reducing energy loss.

[0054] It is easy for those skilled in the art to understand that, on the premise of no conflict, the advantageous technical features of the above various methods can be freely combined and superimposed.

[0055] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. The above is only the preferred implementation manner of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can still be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An air cycle machine, comprising a turbine, the turbine comprising a turbine cover (1), characterized in that: The outer wall surface of the turbine cover (1) is surrounded by a spiral pipe (2), and the inner hole of the spiral pipe (2) is used to fill with a fluid for heating the turbine cover (1).

2. The air cycle machine according to claim 1, characterized in that: The spiral pipe (2) comprises a first pipe section (201) and a second pipe section (202); the end of the first pipe section (201) is connected to the beginning of the second pipe section (202) and is located at the first end (1021) of the turbine cover (1); the beginning of the first pipe section (201) and the end of the second pipe section (202) are both located at the second end (1022) of the turbine cover (1); and the flow direction of the fluid in the first pipe section (201) is opposite to the flow direction in the second pipe section (202).

3. The air cycle machine according to claim 1, characterized in that: The spiral pipe (2) is in surface contact with the outer wall of the turbine cover (1).

4. The air cycle machine according to claim 2, characterized in that: Each circle of tubes formed by the first section of tube (201) surrounding the turbine cover (1) is arranged at intervals from each circle of tubes formed by the second section of tube (202) surrounding the turbine cover (1).

5. The air cycle machine according to claim 1, characterized in that: The air cycle machine further comprises a compressor volute (3), and the inlet of the spiral duct (2) is connected to the outlet of the compressor volute (3) via an inlet pipe (601).

6. The air cycle machine according to claim 1, characterized in that: The air cycle machine further comprises a turbine volute (4), and the outlet of the spiral duct (2) is connected to the inner cavity of the turbine volute (4) via an outlet pipe (602).

7. The air cycle machine according to any one of claims 1 to 6, characterized in that: The turbine cover (1) comprises a turbine cover (101) and an air guide section (102) connected to the outlet end of the turbine cover (101); one end of the air guide section (102) connected to the turbine cover (101) is an air inlet end, and the other end is an air outlet end; and the wall thickness of the air guide section (102) gradually becomes thinner from the air inlet end to the air outlet end.

8. The air cycle machine according to claim 7, characterized in that: The spiral duct (2) is interference fit around the air guide section (102).

9. The air cycle machine according to claim 7, characterized in that: From the air inlet end to the air outlet end, the flow area of ​​the spiral duct (2) gradually increases.

10. The air cycle machine according to claim 7, characterized in that: The inner diameter of the spiral duct (2) is d1, the inner diameter of the air guide section (102) is d2, and 0.1≤d1 / d2≤0.2.

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