Air outlet structure of air cycle machine and air cycle machine

Abstract

The invention provides an air outlet structure of an air cycle machine and the air cycle machine, the air outlet structure comprises an air outlet piece and an air entraining structure, the air outlet piece is provided with a turbine air outlet channel, more than two heat exchange wires which are sequentially arranged at intervals are arranged on the air outlet piece, and an air passing channel is formed by the interval between every two adjacent heat exchange wires. And the air entraining structure is used for introducing heat exchange air to the heat exchange wires, so that the air outlet piece can exchange heat with the heat exchange air through the heat exchange wires. According to the technical scheme, the heat exchange wires can increase the heat exchange area of the air outlet piece, so that the heat exchange efficiency of the air outlet piece and the heat exchange air is improved, and the anti-icing effect of the air outlet piece can be improved. In addition, the heat exchange structure formed by the heat exchange wires can disturb incoming flow to generate vortex, so that the heat exchange efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of air cycle machines, and in particular relates to an air outlet structure of an air cycle machine and the air cycle machine. Background Art

[0002] The air cycle machine is used for compressed air circulation refrigeration. The air cycle machine is driven by high-pressure gas to drive the turbine to rotate the rotor. The turbine and the compressor wheel are coaxial. After the compressor wheel compresses the air, the air temperature and pressure increase and enters the compressor volute. Then the high-temperature and high-pressure air in the compressor volute passes through the turbine volute and enters the nozzle to increase the speed, reduce the pressure and drive the turbine to cool the turbine expanded air.

[0003] The air cycle machine has an air outlet part such as an air outlet pipe, and the air outlet part has a turbine air outlet channel, through which the air cycle machine discharges air. Since the gas temperature in the turbine air outlet channel is relatively low, the temperature of the air outlet part is also relatively low, and it is easy to freeze. At present, a high-temperature heat exchange gas is generally introduced to the air outlet part through an air bleed structure to perform heat exchange on the air outlet part to prevent freezing. However, the heat exchange efficiency of this heat exchange method is currently low and needs to be further improved. Summary of the invention

[0004] Therefore, the present invention provides an air outlet structure of an air cycle machine and an air cycle machine, and the main technical problem to be solved is: how to improve the heat exchange efficiency between the introduced heat exchange gas and the air outlet component.

[0005] In order to solve the above problems, the present invention provides an air outlet structure of an air cycle machine, which includes an air outlet member and an air bleed structure, wherein the air outlet member has a turbine air outlet passage, and the air outlet member is provided with two or more heat exchange wires arranged in sequence at intervals, and the interval between two adjacent heat exchange wires forms an air outlet passage;

[0006] The air introduction structure is used to introduce heat exchange gas into each of the heat exchange wires, so that the air outlet member can perform heat exchange with the heat exchange gas through each of the heat exchange wires.

[0007] In some embodiments, each of the heat exchange wires is a round wire with a diameter of d, wherein:

[0008] The distance between two adjacent heat exchange wires is S, and both d and S satisfy: Wherein, a=6.45~6.7, b=2.5~2.65, and the units of d and S are both millimeters;

[0009] And / or, the number of the heat exchange wires is N, d 2 *N+c1*d*N-c2*d=c3, where c1=9.1~9.30, c2=32~34, c3=87~95, and the unit of d is millimeter.

[0010] In some embodiments, each of the heat exchange wires is bent to form an undulating structure; and each of the heat exchange wires is connected to the air outlet member through one side of its undulating direction.

[0011] In some embodiments, each of the heat exchange wires is in the shape of a sine wave; for a single heat exchange wire, the heat exchange wire forms a first arc segment at the crest and a second arc segment at the trough, and for the adjacent first arc segment and second arc segment on the heat exchange wire, the height difference between the centers of the first arc segment and the second arc segment is h1, and half of the wavelength of the sine wave is w; wherein, h1=(1.2-1.5)*w, and the units of both h1 and w are millimeters.

[0012] In some embodiments, the air entraining structure includes a heat exchange cavity disposed on the gas outlet member, the air entraining structure introduces heat exchange gas through the heat exchange cavity, and the heat exchange cavity also has an air outlet;

[0013] Wherein, each of the heat exchange wires is located in the heat exchange cavity, and each of the heat exchange wires is connected to the cavity wall of the heat exchange cavity, so as to be connected to the air outlet component through the cavity wall of the heat exchange cavity.

[0014] In some embodiments, the heat exchange chamber has an air inlet, and the heat exchange gas is introduced into the heat exchange chamber through the air inlet; the heat exchange chamber has a first chamber wall and a second chamber wall relative to each other, and the air inlet is arranged on the first chamber wall; wherein, when each of the heat exchange wires is bent to form an undulating structure, each of the heat exchange wires is arranged on the second chamber wall through one side of its own undulating direction, and the other side of the undulating direction of each of the heat exchange wires protrudes from the second chamber wall.

[0015] In some embodiments, the heat exchange cavity is an annular cavity disposed within the wall thickness of the gas outlet member, and the annular cavity is disposed around the center line of the turbine gas outlet passage;

[0016] Each of the heat exchange wires is annular and is sleeved on the annular cavity wall of the annular cavity.

[0017] In some embodiments, the air bleed structure includes an air bleed pipe, and the air bleed structure introduces the heat exchange gas through the air bleed pipe.

[0018] In some embodiments, the air duct includes a first pipe segment and a second pipe segment connected to each other, the air duct is arranged on the air outlet piece, the air duct introduces heat exchange gas from the outside through the end of the first pipe segment facing away from the second pipe segment, and the air duct guides the introduced heat exchange gas to each of the heat exchange wires through the end of the second pipe segment facing away from the first pipe segment; the first pipe segment and the second pipe segment are connected by an arc-shaped pipe segment, wherein the radius of the arc-shaped pipe segment is R, the inner hole of the air duct is a circular hole, and the diameter of the circular hole is D, wherein R=16~18 mm, and D=8~9.5 mm.

[0019] In some embodiments, when the air bleed structure includes a heat exchange cavity arranged on the air outlet component, and each of the heat exchange wires is located in the heat exchange cavity, each of the heat exchange wires is bent to form an undulating structure, each of the heat exchange wires is connected to the cavity wall of the heat exchange cavity through one side of its own undulating direction, and the other side of the undulating direction of each of the heat exchange wires protrudes from the cavity wall, the air bleed structure introduces the heat exchange gas into the heat exchange cavity through the air bleed pipe, so that the heat exchange cavity introduces the heat exchange gas through the air bleed pipe; the other side of the undulating direction of each of the heat exchange wires protrudes from the height of the cavity wall h2, the spacing between two adjacent heat exchange wires is S, and the number of the heat exchange wires is N; the inner hole of the air bleed pipe is a circular hole, and the diameter of the circular hole is D; wherein, The units of h2, S and D are all millimeters.

[0020] The present invention further provides an air cycle machine, comprising the air outlet structure of any one of the above-mentioned air cycle machines.

[0021] The air outlet structure of an air cycle machine and the air cycle machine provided by the present invention have the following beneficial effects:

[0022] 1. Each heat exchange wire can increase the heat exchange area of ​​the outlet part to improve the heat exchange efficiency between the outlet part and the heat exchange gas, thereby improving the anti-icing effect of the outlet part. In addition, the air passage formed between two adjacent heat exchange wires is conducive to the flow of air flow, thereby further improving the heat exchange efficiency.

[0023] 2. The heat exchange structure formed by each heat exchange wire can disturb the incoming flow to generate eddy currents, thereby increasing the heat exchange efficiency. In addition, the undulating structure design of the heat exchange wire can absorb sound and vibration very efficiently. When the sound is transmitted to the surface of the heat exchange wire, the heat exchange wire will vibrate, thereby converting the sound into heat energy, which has the effect of reducing vibration and noise.

[0024] 3. By setting R=16-18 mm and D=8-9.5 mm of the air duct, the air duct can have a fundamental frequency resonance peak with a smaller sound pressure level, and the frequency response of the first-order resonance frequency of the air duct can be reduced, thereby reducing the vibration and noise of the air duct. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. The drawings described below are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0026] Figure 1 is a cross-sectional view of an air cycle machine provided by one embodiment of the present invention;

[0027] Figure 2 is a schematic diagram reflecting the structure of a single heat exchange wire provided by an embodiment of the present invention;

[0028] Figure 3 yes Figure 2 The enlarged schematic diagram of point A in the middle;

[0029] Figure 4 It is a schematic diagram reflecting the arrangement of two adjacent heat exchange wires provided by an embodiment of the present invention;

[0030] Figure 5 It is a function graph of the sound pressure level Lp of the fundamental frequency resonance peak of the air duct and R and D;

[0031] Figure 6 A schematic diagram showing the operating frequency of the air bleed tube with the first-order fundamental frequency resonance peak between 1250 Hz and 1550 Hz when R=17 and D=9;

[0032] Figure 7 A schematic diagram showing the operating frequency of the first-order fundamental frequency resonance peak of the air bleed tube between 0-9000 Hz when R=17 and D=9.

[0033] The accompanying drawings are marked as follows:

[0034] 1. Air outlet part; 2. Heat exchange wire; 3. Turbine; 4. Air bleed pipe; 5. Compressor volute; 6. Compressor wheel; 7. Turbine volute; 8. Nozzle; 11. Turbine wheel cover; 12. Sleeve; 21. First arc segment; 22. Second arc segment; 23. Air duct; 41. First pipe section; 42. Second pipe section; 43. Arc-shaped pipe section; 100. Turbine air outlet channel; 101. Heat exchange cavity; 102. Air bleed port; 103. Air outlet; 111. Air outlet pipe; 1011. First cavity wall; 1012. Second cavity wall; 201. One side of the undulating direction of the heat exchange wire; 202. The other side of the undulating direction of the heat exchange wire. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0037] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0038] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0039] See also Figure 1-2As shown, according to an embodiment of the present invention, an air outlet structure of an air cycle machine is provided, which includes an air outlet member 1 and an air bleed structure. The air outlet member 1 has a turbine air outlet passage 100, and the air outlet member 1 is provided with more than two heat exchange wires 2 arranged in sequence, and the interval between two adjacent heat exchange wires 2 forms an air passage 23. The above-mentioned air bleed structure is used to introduce heat exchange gas into each heat exchange wire 2, so that the air outlet member 1 can perform heat exchange with the heat exchange gas through each heat exchange wire 2. In some embodiments, the above-mentioned heat exchange gas can be the gas inside the compressor volute 5 of the air cycle machine. Among them, the gas inside the compressor volute 5 is a high-temperature gas. When the gas inside the compressor volute 5 is introduced into each heat exchange wire 2, it can use its own high temperature to perform heat exchange with each heat exchange wire 2.

[0040] In the above example, each heat exchange wire 2 can increase the heat exchange area of ​​the gas outlet 1 to improve the heat exchange efficiency between the gas outlet 1 and the heat exchange gas, thereby improving the anti-icing effect of the gas outlet 1. In addition, the air passage 23 formed between two adjacent heat exchange wires 2 is conducive to the flow of airflow, thereby further improving the heat exchange efficiency.

[0041] Among them, compared with the heat exchange parts made of thin metal heat exchange fins, at the same energy efficiency value, the heat exchange structure formed by the heat exchange wires 2 can save at least 50% of the materials required to increase the heat exchange surface area. Accordingly, the heat exchange efficiency can be significantly improved while keeping the material usage unchanged.

[0042] In some embodiments, the heat exchange wires 2 mentioned above may all be metal wires.

[0043] It should be noted here that the heat exchange structure formed by the heat exchange wires 2 may sometimes be referred to as a heat exchange wire mesh, although the heat exchange wire mesh formed by the heat exchange wires 2 does not have a mesh structure of a conventional wire mesh.

[0044] The heat exchange structure formed by the heat exchange wires 2 can disturb the incoming flow to generate vortices, thereby increasing the heat exchange efficiency, and is very suitable for microchannel heat exchange. Among them, the heat exchange structure formed by the heat exchange wires 2 can also promote the stability of the induced air flow, reduce larger vortices and dead zones, and enable the heat exchange structure to suppress and eliminate noise. Among them, the heat exchange structure formed by the heat exchange wires 2 suppresses and eliminates noise in the following three mechanisms: 1. When the airflow passes through the surface of the heat exchange structure, the heat exchange structure will interfere with the gas flow on the blunt body surface and reduce the local flow impact velocity; 2. The heat exchange structure will decompose the incoming flow into small vortices, thereby causing the downstream spanwise shedding vortex to change, reducing the orderliness of the vortex, thereby reducing certain types of turbulence or vibration; 3. The heat exchange structure will move the vortex away from the blunt body surface, disperse the sound wave energy, and thus reduce the acoustic emission efficiency.

[0045] In some embodiments, Figure 4As shown, each of the aforementioned heat exchange wires 2 can be a round wire with a diameter of d, wherein the distance between two adjacent heat exchange wires 2 is S, and both d and S satisfy: a=6.45~6.7,b=2.5~2.65,the units of d and S are both millimeters.

[0046] In the above example, by using The relationship between the diameter d of the heat exchange wire and the spacing S between two adjacent heat exchange wires can be limited so that the heat exchange wire 2 has an appropriate spacing S when the diameter d is set. In this way, the air passage 23 between two adjacent heat exchange wires 2 can maintain an appropriate circulation space, thereby avoiding that the circulation space of the air passage 23 between two adjacent heat exchange wires 2 is too large, which leads to a reduction in the number of heat exchange wires 2 set in a limited space, resulting in a reduction in the heat exchange area and affecting the heat exchange efficiency; it can also avoid that the circulation space of the air passage 23 between two adjacent heat exchange wires 2 is too small, which leads to obstruction of airflow, reduces the air volume and causes lower heat exchange efficiency.

[0047] In some embodiments, the number of the heat exchange wires 2 may be N, and N and d satisfy:

[0048] d 2 *N+c1*d*N-c2*d=c3.

[0049] Among them, c1=9.1~9.30, c2=32~34, c3=87~95, and the unit of d is millimeter.

[0050] In the above example, by making d 2 *N+c1*d*N-c2*d=c3, which can define the relationship between the diameter d of the heat exchange wire 2 and the number N of the heat exchange wires 2, so that the heat exchange wire 2 has a suitable diameter d when the number N is set. Specifically, when each heat exchange wire 2 is installed in a limited heat exchange space, the number N of the heat exchange wires 2 can be predetermined, and the number N of the heat exchange wires 2 should satisfy: the heat exchange wires 2 can fill the heat exchange surface of the air outlet 1 to improve the heat exchange efficiency. Among them, when the number of heat exchange wires 2 has been determined, the above formula d 2 *N+c1*d*N-c2*d=c3 The diameter d of each heat exchange wire 2 is determined so that the diameter of each heat exchange wire 2 is not too large to affect the flow space of the air passage 23 between two adjacent heat exchange wires 2, resulting in obstruction of air flow, reduced air volume and lower heat exchange efficiency. The diameter of each heat exchange wire 2 is also not too small to reduce the heat exchange area of ​​the heat exchange wire 2, resulting in lower heat exchange efficiency.

[0051] In some embodiments, each of the aforementioned heat exchange wires 2 can be bent to form an undulating structure. Each of the heat exchange wires 2 is connected to the gas outlet member 1 through one side of its undulating direction.

[0052] In the above example, if Figure 3 As shown, the present invention designs the heat exchange wire 2 into an undulating structure, so that crests and troughs are formed on the heat exchange wire 2, and the heat exchange wire 2 is connected to the outlet 1 through the crest side or the trough side. Compared with the straight heat exchange wire 2, the crest or trough of the heat exchange wire 2 of the present invention has a larger connection space, so it is easier to connect the heat exchange wire 2 to the outlet 1. In addition, the undulating structure design of the heat exchange wire 2 allows it to absorb sound and vibration very efficiently. When sound is transmitted to the surface of the heat exchange wire 2, the heat exchange wire 2 will vibrate, thereby converting the sound into heat energy, which has the effect of reducing vibration and noise.

[0053] In some embodiments, Figure 3 As shown, each of the aforementioned heat exchange wires 2 can be in a sine wave shape. For a single heat exchange wire 2, the heat exchange wire 2 forms a first arc segment 21 at the wave crest and a second arc segment 22 at the wave trough. For the adjacent first arc segment 21 and second arc segment 22 on the heat exchange wire 2, the height difference between the centers of the first arc segment 21 and the second arc segment 22 is h1, and half of the wavelength of the sine wave is w. Wherein, h1 = (1.2-1.5) * w, and the units of h1 and w are both millimeters.

[0054] In the above example, by limiting h1=(1.2-1.5)*w, the wave amplitude height of the heat exchange wire 2 is prevented from being too small, resulting in a small heat exchange area of ​​the heat exchange wire 2 and affecting the heat exchange efficiency; and the wave amplitude height of the heat exchange wire 2 is prevented from being too large, occupying more space, which is not conducive to installation in a narrow space.

[0055] In some embodiments, Figure 3 As shown, the radius of the first arc segment 21 and the second arc segment 22 are both r, r = 0.8w ~ 1.3w. By limiting r = 0.8w ~ 1.3w, the wave height of the heat exchange wire 2 is limited. The main purpose of this design is to prevent the wave height of the heat exchange wire 2 from being too small, resulting in a small heat exchange area of ​​the heat exchange wire 2 and affecting the heat exchange efficiency; and to prevent the wave height of the heat exchange wire 2 from being too large to occupy more space, which is not conducive to installation in a narrow space.

[0056] In some embodiments, Figure 1 and Figure 2As shown, the aforementioned air entrainment structure may include a heat exchange cavity 101 disposed on the air outlet member 1, and the air entrainment structure introduces heat exchange gas through the heat exchange cavity 101. The heat exchange cavity 101 also has an air outlet 103, so that the introduced heat exchange gas can flow in the heat exchange cavity 101 to form a flowing airflow, which is beneficial to the heat exchange of the heat exchange wire 2. In a specific application example, the air outlet 103 can be connected to the inside of the turbine volute 7 of the air cycle machine. The gas after heat exchange in the heat exchange cavity 101 can enter the inside of the turbine volute 7 through the air outlet 103 to realize gas recovery.

[0057] The aforementioned heat exchange wires 2 are located in the heat exchange cavity 101 , and the heat exchange wires 2 are connected to the cavity wall of the heat exchange cavity 101 , so as to be connected to the gas outlet member 1 through the cavity wall of the heat exchange cavity 101 .

[0058] In the above example, the heat exchange chamber 101 gathers the heat exchange gas inside, and by arranging each heat exchange wire 2 in the heat exchange chamber 101, the efficiency of heat exchange between each heat exchange wire 2 and the heat exchange gas can be improved, thereby further improving the heat exchange efficiency between the air outlet 1 and the heat exchange gas.

[0059] In some embodiments, Figure 2 and Figure 3 As shown, the aforementioned heat exchange cavity 101 has an air inlet 102, and the aforementioned heat exchange gas is introduced into the heat exchange cavity 101 through the air inlet 102. The heat exchange cavity 101 has a first cavity wall 1011 and a second cavity wall 1012 opposite to each other, and the aforementioned air inlet 102 is arranged on the first cavity wall 1011. Among them, when each heat exchange wire 2 is bent to form an undulating structure, each heat exchange wire 2 is arranged on the second cavity wall 1012 through one side 201 of the undulating direction, and the other side 202 of each heat exchange wire 2 in the undulating direction protrudes from the second cavity wall 1012.

[0060] In the above example, the air inlet 102 and the heat exchange wire 2 are located on opposite sides of the heat exchange chamber 101, so that the airflow from the air inlet 102 can impact the side of the heat exchange wire 2 away from the second chamber wall 1012 when flowing into the heat exchange chamber 101. Since the heat exchange wire 2 has a wave-like undulating structure, the side of the heat exchange wire 2 away from the second chamber wall 1012 can be elastically deformed to absorb sound and vibration when impacted by the airflow from the air inlet 102, thereby achieving a noise reduction effect.

[0061] In some embodiments, each of the heat exchange wires 2 can be brazed to the second cavity wall 1012 of the heat exchange cavity 101 through one side of the undulating direction. The melted brazing material after brazing will fill the gap between the heat exchange wire 2 and the second cavity wall 1012, ensuring that the second cavity wall 1012 and the heat exchange wire 2 are in contact with each other to increase the heat transfer area.

[0062] In some embodiments, Figure 1 and Figure 2 As shown, the aforementioned heat exchange cavity 101 can be an annular cavity arranged in the wall thickness of the gas outlet member 1, and the annular cavity is arranged around the center line of the turbine gas outlet channel 100. The aforementioned heat exchange wires 2 are all annular and are sleeved on the annular cavity wall of the annular cavity.

[0063] In the above example, the annular heat exchange cavity 101 can improve the heat exchange efficiency between the heat exchange gas and the gas outlet 1. By designing the heat exchange wire 2 to be annular and sleeved on the annular cavity wall of the annular cavity, the heat exchange area of ​​the heat exchange wire 2 is increased.

[0064] In some embodiments, the aforementioned gas outlet member 1 may include a turbine wheel cover 11 and a sleeve 12, wherein the turbine wheel cover 11 has a gas outlet pipe 111. The sleeve 12 is sleeved on the outer side of the gas outlet pipe 111, and the aforementioned annular cavity is formed between the two. The inner hole of the gas outlet pipe 111 forms at least one section of the aforementioned turbine gas outlet channel 100.

[0065] In the above example, by designing the gas outlet member 1 as a combined member, it is advantageous to form the aforementioned annular heat exchange cavity 101 within the wall thickness of the gas outlet member 1 .

[0066] It should be noted here that the above-mentioned sleeve 12 may also be referred to as an outlet guide member in some occasions.

[0067] In order to facilitate the introduction of heat exchange gas into the heat exchange chamber 101, in some embodiments, as Figure 1 As shown, the aforementioned air bleed structure may include an air bleed pipe 4 , and the air bleed structure introduces heat exchange gas through the air bleed pipe 4 .

[0068] The heat exchange gas mentioned above can be high-temperature and high-pressure gas compressed by the compressor wheel 6 of the air cycle machine. The air bleed pipe 4 realizes heat exchange with the low-temperature wall of the turbine outlet passage 100 by introducing the heat exchange gas of the high-temperature and high-pressure gas, and increases the wall temperature of the turbine outlet passage 100 by fluid heat transfer and solid heat transfer, thereby limiting the occurrence of icing of the outlet part 1. However, the air bleed pipe 4 may resonate under certain conditions, which may cause unnecessary vibration, thereby affecting the structural integrity or causing noise problems. A high fundamental frequency resonant sound pressure level will cause high-level vibration of the air bleed pipe 4, which may cause material fatigue and damage. A lower fundamental frequency resonant sound pressure level means that the amplification effect of acoustic energy at a specific frequency is smaller, which helps to reduce the vibration and noise of the air bleed pipe 4.

[0069] In order to make the air duct 4 have a lower fundamental frequency resonant sound pressure level and reduce the vibration and noise in the air duct 4, in some embodiments, as Figure 1As shown, the aforementioned air duct 4 includes a first pipe section 41 and a second pipe section 42 connected to each other, and the air duct 4 is arranged on the air outlet 1. The air duct 4 introduces heat exchange gas from the outside through the end of the first pipe section 41 that is away from the second pipe section 42, and the air duct 4 guides the introduced heat exchange gas to each heat exchange wire 2 through the end of the second pipe section 42 that is away from the first pipe section 41. The first pipe section 41 and the second pipe section 42 are connected by an arc-shaped pipe section 43. The radius of the arc-shaped pipe section 43 is R, the inner hole of the air duct 4 is a circular hole, and the diameter of the circular hole is D. R = 16 to 18 mm, and D = 8 to 9.5 mm.

[0070] In the above example, by setting R=16-18 mm and D=8-9.5 mm, the air duct 4 can have a fundamental frequency resonance peak with a smaller sound pressure level, and the frequency response of the first-order resonance frequency of the air duct 4 can be reduced, thereby reducing the vibration and noise of the air duct 4, thereby solving the problem of high-level noise that may be caused by the airflow of the air duct 4.

[0071] The following is an analysis of the acquisition process of the above R and D. Specifically, in order to solve the sound pressure level of the fundamental frequency resonance peak of the air bleed pipe 4, multiple groups of simulations can be performed by changing the radius R of the arc-shaped pipe section 43 and the inner diameter D of the air bleed pipe 4, and the influence of the two variables R and D on the resonance peak is obtained, and the mathematical relationship between R and D and the dependent variable fundamental frequency resonance peak is obtained through polynomial regression.

[0072] Since changing the wall thickness T of the air duct 4 will only have a slight effect on the resonance, the air duct 4 is optimized and designed only by R and D to reduce the sound pressure level of its fundamental frequency resonance peak. The frequency response of the air duct 4 is represented by the sound pressure level Lp of the air duct 4:

[0073]

[0074]

[0075] Where P ref represents the reference pressure when the air is 20uPa, p is the sound pressure (Pa), and * represents a conjugate complex number. The model parameters of the air duct are shown in Table 1.

[0076] Table 1

[0077] name value Young's modulus of tube wall 6.84e10[Pa] Poisson's ratio of tube wall 0.3316 Ambient temperature 184(℃) Environmental pressure 4.46~4.49(bara) Average flow rate 52.7(m / s)

[0078] Through simulation calculation and function fitting, it is found that the sound pressure level Lp of the fundamental frequency resonance peak of the air duct 4 has the following relationship with R and D:

[0079] Lp=a1+a2*R+a3*D+a4*R2+a5*D2+a6*D*R;

[0080] Among them, a1 = 246.5 ± 8.64, a2 = -5.479 ± 0.79, a3 = -2.758 ± 0.8, a4 = 0.154 ± 0.02, a5 = 0.095 ± 0.04, a6 = 0.031 ± 0.03.

[0081] The function graphs of Lp, R and D are as follows: Figure 5 As shown by Figure 5 It can be seen that within a given function range, when R=16-18 mm and D=8-9.5 mm, the air duct 4 has a fundamental frequency resonance peak with a relatively small sound pressure level.

[0082] Figure 6 and Figure 7 Both show the schematic diagram between the first-order fundamental frequency resonance peak value and the operating frequency of the air duct 4 when R=17 and D=9. Figure 6 It can be seen from FIG. 1 that when the operating frequency range is between 1250 Hz and 1550 Hz, the air duct 4 has the maximum resonance peak at 1425 Hz. Figure 7 It can be seen that when the operating frequency range is between 0-9000 Hz, the air duct 4 has six resonance peaks of the first-order natural frequency. Figure 6 and Figure 7 It can be seen that when R=17 and D=9, the first-order fundamental frequency resonance peak of the air duct 4 is relatively small, so that the air duct 4 has reduced vibration and noise.

[0083] In some embodiments, Figure 1-Figure 3 As shown, when the air bleed structure includes a heat exchange cavity 101 arranged on the air outlet member 1, and each heat exchange wire 2 is located in the heat exchange cavity 101, each heat wire is bent to form an undulating structure, each heat exchange wire 2 is connected to the cavity wall of the heat exchange cavity 101 through one side 201 of its own undulating direction, and the other side 202 of each heat exchange wire in the undulating direction protrudes from the cavity wall, the air bleed structure introduces the heat exchange gas into the heat exchange cavity 101 through the air bleed pipe 4, so that the heat exchange cavity 101 introduces the heat exchange gas through the air bleed pipe 4; the other side 202 of each heat exchange wire in the undulating direction protrudes from the height of the cavity wall h2, the distance between two adjacent heat exchange wires 2 is S, and the number of heat exchange wires 2 is N. The inner hole of the air bleed pipe 4 is a circular hole, and the diameter of the circular hole is D. Among them, The units of h2, S and D are all millimeters.

[0084] In the above example, by using The relationship between the flow cross-sectional area of ​​the air passage 23 between two adjacent heat exchange wires 2 and the flow cross-sectional area of ​​the air duct 4 can be limited so that the gas flow flowing in from the air duct 4 can fully flow into the air passage 23 between each two adjacent heat exchange wires 2, thereby avoiding the air flow being blocked due to the flow cross-sectional area of ​​the air passage 23 between two adjacent heat exchange wires 2 being too small, which will affect the air volume and reduce the heat exchange efficiency.

[0085] It should be noted here that: in some implementations, the above h2 is equal to the above h1.

[0086] In some embodiments, the present invention further provides an air cycle machine, which may include any of the above-mentioned air cycle machine outlet structures. In particular, because the air cycle machine adopts the above-mentioned outlet structure, the heat exchange wire 2 can increase the heat exchange area of ​​the outlet member 1 to improve the heat exchange efficiency between the outlet member 1 and the heat exchange gas, thereby improving the anti-icing effect of the outlet member 1.

[0087] The working principle of the air cycle machine of the present invention is as follows: Figure 1 As shown, the air cycle machine is used for compressed air circulation refrigeration. The air cycle machine is driven by high-pressure gas to drive the turbine 3 to rotate the rotor. The turbine 3 and the compressor wheel 6 are coaxial. After the compressor wheel 6 compresses the air, the air temperature and pressure increase and enters the compressor volute 5. Subsequently, the high-temperature and high-pressure air in the compressor volute 5 passes through the turbine volute 7 and enters the nozzle 8 to increase the speed, reduce the pressure and drive the turbine 3 to make the turbine 3 expand the air for refrigeration.

[0088] It is easy for those skilled in the art to understand that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions 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 description is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention. These improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. An air outlet structure of an air cycle machine, characterized in that: The invention comprises an air outlet member (1) and an air ducting structure, wherein the air outlet member (1) has a turbine air outlet passage (100), and the air outlet member (1) is provided with two or more heat exchange wires (2) arranged in sequence at intervals, and the interval between two adjacent heat exchange wires (2) forms an air outlet passage (23); The air introduction structure is used to introduce heat exchange gas into each of the heat exchange wires (2), so that the air outlet member (1) can perform heat exchange with the heat exchange gas through each of the heat exchange wires (2).

2. The air outlet structure of the air cycle machine according to claim 1, characterized in that: Each of the heat exchange wires (2) is a round wire with a diameter of d, wherein: The distance between two adjacent heat exchange wires (2) is S, and both d and S satisfy: Wherein, a=6.45~6.7, b=2.5~2.65, and the units of d and S are both millimeters; And / or, the number of the heat exchange wires is N, d 2 *N+c1*d*N-c2*d=c3, where c1=9.1~9.30, c2=32~34, c3=87~95, and the unit of d is millimeter.

3. The air outlet structure of the air cycle machine according to claim 1 or 2, characterized in that: Each of the heat exchange wires (2) is bent to form an undulating structure; each of the heat exchange wires (2) is connected to the air outlet member (1) via one side (201) in the undulating direction.

4. The air outlet structure of the air cycle machine according to claim 3, characterized in that: Each of the heat exchange wires (2) is in the shape of a sine wave; for a single heat exchange wire (2), the heat exchange wire (2) forms a first arc segment (21) at the wave crest and a second arc segment (22) at the wave trough; for adjacent first arc segments (21) and second arc segments (22) on the heat exchange wire (2), the height difference between the centers of the first arc segment (21) and the second arc segment (22) is h1, and half of the wavelength of the sine wave is w; wherein h1=(1.2-1.5)*w, and the units of h1 and w are both millimeters.

5. The air outlet structure of the air cycle machine according to claim 1, 2 or 4, characterized in that: The air entraining structure comprises a heat exchange cavity (101) arranged on the gas outlet member (1), the air entraining structure introduces heat exchange gas through the heat exchange cavity (101), and the heat exchange cavity (101) also has an outlet (103); Wherein, each of the heat exchange wires (2) is located in the heat exchange cavity (101), and each of the heat exchange wires (2) is connected to the cavity wall of the heat exchange cavity (101) so as to be connected to the air outlet component (1) through the cavity wall of the heat exchange cavity (101).

6. The air outlet structure of the air cycle machine according to claim 5, characterized in that: The heat exchange chamber (101) has an air inlet (102), and the heat exchange chamber (101) introduces the heat exchange gas through the air inlet (102); the heat exchange chamber (101) has a first chamber wall (1011) and a second chamber wall (1012) opposite to each other, and the air inlet (102) is arranged on the first chamber wall (1011); wherein, when each of the heat exchange wires (2) is bent to form an undulating structure, each of the heat exchange wires (2) is arranged on the second chamber wall (1012) through one side (201) in the undulating direction, and the other side (202) of each of the heat exchange wires in the undulating direction protrudes from the second chamber wall (1012).

7. The air outlet structure of the air cycle machine according to claim 5, characterized in that: The heat exchange cavity (101) is an annular cavity arranged in the wall thickness of the gas outlet member (1), and the annular cavity is arranged around the center line of the turbine gas outlet channel (100); Each of the heat exchange wires (2) is annular and is sleeved on the annular cavity wall of the annular cavity.

8. The air outlet structure of the air cycle machine according to any one of claims 1-2, 4, 6-7, characterized in that: The air bleed structure comprises an air bleed pipe (4), and the air bleed structure introduces heat exchange gas through the air bleed pipe (4).

9. The air outlet structure of the air cycle machine according to claim 8, characterized in that: The air duct (4) comprises a first pipe section (41) and a second pipe section (42) connected to each other. The air duct (4) is arranged on the air outlet member (1). The air duct (4) introduces heat exchange gas from the outside through the end of the first pipe section (41) facing away from the second pipe section (42), and the air duct (4) guides the introduced heat exchange gas to each of the heat exchange wires (2) through the end of the second pipe section (42) facing away from the first pipe section (41); the first pipe section (41) and the second pipe section (42) are connected through an arc-shaped pipe section (43), wherein the radius of the arc-shaped pipe section (43) is R, the inner hole of the air duct (4) is a circular hole, and the diameter of the circular hole is D, wherein R=16-18 mm, and D=8-9.5 mm.

10. The air outlet structure of the air cycle machine according to claim 8, characterized in that: When the air entrainment structure comprises a heat exchange cavity (101) arranged on the air outlet member (1), and each of the heat exchange wires (2) is located in the heat exchange cavity (101), each of the heat exchange wires (2) is bent to form an undulating structure, each of the heat exchange wires (2) is connected to the cavity wall of the heat exchange cavity (101) through one side (201) in the undulating direction, and the other side (202) in the undulating direction of each of the heat exchange wires protrudes from the arranged cavity wall, the The air bleed structure introduces the heat exchange gas into the heat exchange cavity (101) through the air bleed pipe (4), so that the heat exchange cavity (101) introduces the heat exchange gas through the air bleed pipe (4); the other side (202) of the undulating direction of each heat exchange wire protrudes above the height of the cavity wall h2, the spacing between two adjacent heat exchange wires (2) is S, and the number of the heat exchange wires (2) is N; the inner hole of the air bleed pipe (4) is a circular hole, and the diameter of the circular hole is D; wherein, The units of h2, S and D are all millimeters.

11. An air cycle machine, characterized in that: An air outlet structure for an air cycle machine comprising any one of claims 1-10.

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