A double-sided intake centrifugal compressor with adjustable intake air flow, an aeroengine

Abstract

The present application discloses a double-sided intake centrifugal compressor with adjustable intake air flow and an aero-engine. The double-sided intake centrifugal compressor includes a centrifugal impeller, a gas collecting chamber, two impeller casings, two intake casings, and a displacement actuator mechanism. The centrifugal impeller is a double-sided centrifugal impeller, which includes a hub and blades arranged back-to-back on both sides of the hub, and the blades are radial blades. The two impeller casings are coaxially arranged with the centrifugal impeller and symmetrically arranged on both sides of the centrifugal impeller so as to be movable left and right along the rotation axis of the centrifugal impeller. The gas collecting chamber is communicated with the impeller outlet for collecting the air flow at various circumferential positions of the impeller outlet, converging it to one side and then discharging it along the exhaust port. The displacement actuator mechanism is respectively drivingly connected to the two impeller casings. The adjustment structure of the present application is simple, the flow adjustment accuracy is high, the adjustment range is wide, the stability is good, and the adjustment distance is short, which can meet the requirements of high-precision wide-range adjustment and high-response-speed adjustment.

Description

Technical Field

[0001] The present application relates to the technical field of centrifugal compressors, and in particular, to a double-sided intake centrifugal compressor and an aircraft engine with adjustable intake flow. Background Art

[0002] Centrifugal compressors are widely used in aircraft engines, industrial compressors, etc. Its main function is to compress the gas using the shaft power input by other devices or components to increase the total temperature and total pressure of the gas. The most core component that does work on the gas is the centrifugal impeller. The airflow after the centrifugal impeller does work enters the air collecting chamber, where the gas velocity decreases, the static pressure increases, and finally it is discharged through the compressor outlet. It can be used as an aircraft engine compressor or an industrial compressor to generate high-pressure airflow that meets demand. When it is used as a load simulation device, it is necessary to adjust the compressor airflow size or power consumption under the condition of constant speed. Therefore, it needs to have a mechanism that can adjust the flow rate. One of the existing adjustment methods is to add a row of inlet guide vanes in front of the centrifugal impeller. The number of guide vanes is multiple, and the flow rate is adjusted by adjusting the angle of the inlet guide vanes (see Figure 1 and Figure 2 ). However, this method has a very complex structure. Each blade requires a separate rotating shaft, which drives all blades to rotate together through the linkage ring. The flow area is reduced by rotating the blades to adjust the flow rate. However, the angle of each blade is inconsistent during the adjustment process, which causes distortion of the centrifugal impeller inlet. At the same time, when the rotation angle is too large, the rotating blade itself will cause great losses, which is not conducive to the performance and working stability of the compressor. In addition, due to the existence of idle stroke, the flow regulation accuracy is generally low. At the same time, when using this method, during the minimum flow adjustment process, the angle at which the blades need to rotate is very large, usually reaching 80° to 90°. At this time, there may be interference between blades or between blades and end wall flow channels, resulting in the inability to achieve the desired minimum flow rate. Summary of the invention

[0003] An embodiment of one aspect of the present application provides a double-sided intake centrifugal compressor with adjustable intake flow, so as to solve the technical problems that the flow regulating mechanism of the centrifugal impeller of the existing centrifugal compressor has a complex structure, poor stability, low adjustment accuracy, and cannot achieve the desired minimum flow due to interference.

[0004] The technical solutions adopted in this application are as follows:

[0005] A double-sided intake centrifugal compressor with adjustable intake air flow, comprising a centrifugal impeller, a collector chamber, two impeller shrouds, two intake casings, and a displacement actuator. The centrifugal impeller is a double-sided centrifugal impeller, including a hub and blades arranged back-to-back on both sides of the hub. The blades are radial blades. The two impeller shrouds are coaxially arranged with the centrifugal impeller and symmetrically arranged on both sides of the centrifugal impeller so as to be movable left and right along the rotation axis of the centrifugal impeller. An annular groove for accommodating the blades is provided on one side of each impeller shroud facing the blades. An impeller intake port is formed between the inner annular wall on the side close to the center of the annular groove and the hub of the centrifugal impeller. An impeller outlet port is formed between the outer annular wall on the side far from the center of the annular groove and the hub of the centrifugal impeller. The two intake casings are symmetrically arranged on both sides of the centrifugal impeller and communicate with the impeller intake port to supply air to the centrifugal impeller. The collector chamber communicates with the impeller outlet port and is used to collect the air flow from all circumferential parts of the impeller outlet port, gather it to one side, and then discharge it along the exhaust port. The displacement actuator is respectively drivingly connected to the two impeller shrouds and is used to drive the impeller shrouds on both sides of the centrifugal impeller to move left and right along the rotation axis of the centrifugal impeller, adjust the width L of the impeller intake port and the width L5 of the impeller outlet port on both sides of the centrifugal impeller, change the intake area and outlet area of the centrifugal impeller, and realize the adjustment of the intake air flow under the condition of constant rotational speed of the centrifugal compressor.

[0006] Further, the width L3 of the outlet of the intake casing is greater than the height L2 of the blades of the centrifugal impeller.

[0007] Further, the meridional projection of the inner surface of the impeller shroud is trapezoidal. Among them, the depth L4 from the inner annular wall to the bottom of the annular groove is 1.2 - 2 times the height L2 of the blades, and the depth L6 from the outer annular wall to the bottom of the annular groove is adjusted according to the slope of the hub of the centrifugal impeller.

[0008] Further, the depth L6 from the outer annular wall to the bottom of the annular groove is greater than or equal to the depth L4 from the inner annular wall to the bottom of the annular groove.

[0009] Further, the width L of the impeller intake port and the width L5 of the impeller outlet port on both sides of the centrifugal impeller are the same.

[0010] Further, when the two impeller shrouds move along the rotation axis of the centrifugal impeller to adjust the width L of the impeller intake port and the width L5 of the impeller outlet port, and the centrifugal impeller is opened from the minimum flow state to the maximum flow state, the displacement distance of the impeller shroud is equal to the height L2 of the blades.

[0011] Further, the collector chamber is an integral structure with a partition in the middle. The midline of the partition is in the same plane as the axis of the centrifugal impeller. The gas discharged from the impeller outlet ports on both the left and right sides of the centrifugal impeller respectively flows into both sides of the partition of the collector chamber.

[0012] Furthermore, the partition plate is in an isosceles trapezoid shape, wherein the width of the end of the partition plate facing the centrifugal impeller is smaller than the width of the end far from the centrifugal impeller.

[0013] Furthermore, there is a certain gap between the end of the partition plate facing the centrifugal impeller and the tip of the centrifugal impeller.

[0014] An embodiment of another aspect of the present application further provides an aeroengine, including the double-sided intake centrifugal compressor with adjustable intake air flow.

[0015] Compared with the prior art, the present application has the following beneficial effects:

[0016] The double-sided intake centrifugal compressor with adjustable intake air flow proposed in the present application includes a centrifugal impeller, a gas collecting chamber, two impeller casings, two intake casings, and a displacement actuator. In this embodiment, there is no need for multiple guide vane structures that need to be rotationally adjusted. Only by driving the two impeller casings to move left and right through the displacement actuator, there are few moving parts, the adjustment structure is simple, the flow rate adjustment accuracy is high, the adjustment range is wide, and the stability is good. At the same time, the distance that needs to be adjusted is very short, which can meet the requirements of high-precision wide-range adjustment and also meet the requirements of high-response-speed adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The schematic embodiments and descriptions thereof of the present application are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0018] Figure 1 It is a schematic diagram of the guide vane state when the existing centrifugal compressor controls the guide vane angle to increase the intake air flow.

[0019] Figure 2 It is a schematic diagram of the guide vane state when the existing centrifugal compressor controls the guide vane angle to decrease the intake air flow.

[0020] Figure 3 It is a schematic diagram of the structural principle of the double-sided intake centrifugal compressor with adjustable intake air flow according to the preferred embodiment of the present application.

[0021] Figure 4 It is a schematic diagram of the partial structural principle of the double-sided intake centrifugal compressor with adjustable intake air flow according to the preferred embodiment of the present application.

[0022] Figure 5 It is a schematic diagram of the key design dimensions of the double-sided intake centrifugal compressor with adjustable intake air flow according to the preferred embodiment of the present application.

[0023] Figure 6 It is a three-dimensional structural schematic diagram of the gas collecting chamber.

[0024] Figure 7It is a curve graph showing the corresponding relationship between the power consumed by the centrifugal compressor and the opening degree of the impeller shroud.

[0025] Figure 8 It is a curve graph showing the corresponding relationship between the gas flow rate of the centrifugal compressor and the opening degree of the impeller shroud.

[0026] Figure 9 It is a schematic diagram of the position state of the impeller shroud when the double-sided intake centrifugal compressor with adjustable intake flow rate is in the minimum flow rate state.

[0027] Figure 10 It is a schematic diagram of the position state of the impeller shroud when the double-sided intake centrifugal compressor with adjustable intake flow rate is in the maximum flow rate state.

[0028] In the figure: 1. Air collecting chamber; 11. Partition board; 2. Centrifugal impeller; 21. Hub; 22. Blade; 3. Impeller shroud; 31. Outer annular wall; 32. Inner annular wall; 33. Bottom of annular groove; 34. Annular groove; 4. Intake casing; 5. Impeller intake port; 6. Impeller outlet port. Detailed implementation manners

[0029] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will describe this application in detail with reference to the drawings and in combination with the embodiments.

[0030] Refer to Figure 3 、 Figure 4 and Figure 5, a preferred embodiment of the present application provides a double-sided intake centrifugal compressor with adjustable intake air flow, which includes a centrifugal impeller 2, a collector chamber 1, two impeller shrouds 3, two intake casings 4, and a displacement actuator mechanism. The centrifugal impeller 2 is a double-sided centrifugal impeller, which includes a hub 21 and blades 22 arranged back-to-back on both sides of the hub 21. The blades 22 are radial blades. The two impeller shrouds 3 are coaxially arranged with the centrifugal impeller 2 and symmetrically arranged on both sides of the centrifugal impeller 2 so as to be movable left and right along the rotation axis of the centrifugal impeller 2. On one side of each impeller shroud 3 facing the blade 22, there is an annular groove 34 for accommodating the blade 22. An impeller intake port 5 is formed between the inner annular wall 32 on the side close to the center of the annular groove 34 and the hub 21 of the centrifugal impeller 2. An impeller outlet port 6 is formed between the outer annular wall 31 on the side far from the center of the annular groove 34 and the hub 21 of the centrifugal impeller 2. The two intake casings 4 are symmetrically arranged on both sides of the centrifugal impeller 2 and are connected to the impeller intake port 5 to supply intake air to the centrifugal impeller 2. The collector chamber 1 is connected to the impeller outlet port 6 and is used to collect the air flow from various circumferential positions of the impeller outlet port 6, gather it to one side, and then discharge it along the exhaust port. The displacement actuator mechanism is respectively drivingly connected to the two impeller shrouds 3 and is used to drive the impeller shrouds 3 on both sides of the centrifugal impeller 2 to move left and right along the rotation axis of the centrifugal impeller 2, adjust the width L of the impeller intake port 5 and the width L5 of the impeller outlet port 6 on both sides of the centrifugal impeller 2, change the intake area and outlet area of the centrifugal impeller 2, and realize the adjustment of the intake air flow under the condition that the rotational speed of the centrifugal compressor remains unchanged.

[0031] The double-sided intake centrifugal compressor with adjustable intake air flow proposed in this embodiment includes a centrifugal impeller 2, a collector chamber 1, two impeller shrouds 3, two intake casings 4, and a displacement actuator mechanism. There is no need for multiple guide vane structures that need to be rotationally adjusted in this embodiment. Only by driving the two impeller shrouds 3 to move left and right through the displacement actuator mechanism, it has few moving parts, a simple adjustment structure, high flow adjustment accuracy, a wide adjustment range, good stability. At the same time, the distance that needs to be adjusted is very short, which can meet the requirements of high-precision wide-range adjustment and high-response-speed adjustment.

[0032] Preferably, the width L3 of the outlet of the intake casing 4 is greater than the height L2 of the blade 22 of the centrifugal impeller 2, ensuring that during the movement of the impeller shroud 3, the intake casing 4 always cooperates with the impeller shroud 3 to ensure that the air flow in the intake casing 4 enters the annular groove 34 as much as possible and does not flow outside the impeller shroud 3.

[0033] Preferably, the meridional projection of the inner profile of the impeller shroud 3 is trapezoidal. Among them, the depth L4 from the inner annular wall 32 to the bottom 33 of the annular groove is 1.2 to 2 times the height L2 of the blade 22. The depth L6 from the outer annular wall 31 to the bottom 33 of the annular groove is adjusted according to the slope of the hub 21 of the centrifugal impeller 2. The shape and size design of the impeller shroud 3 is conducive to precise adjustment between the maximum gas flow rate and the minimum gas flow rate.

[0034] Preferably, the depth L6 from the outer annular wall 31 to the bottom 33 of the annular groove is greater than or equal to the depth L4 from the inner annular wall 32 to the bottom 33 of the annular groove. In this embodiment, the size relationship between the depth L6 and the depth L4 is associated with the slope of the hub 21, which is conducive to ensuring that the width L of the impeller inlet 5 and the width L5 of the impeller outlet 6 on both sides of the centrifugal impeller 2 are basically the same. By driving the impeller shrouds 3 on both sides to move left and right through the displacement actuator mechanism, the widths L of the impeller inlets 5 and the widths L5 of the impeller outlets 6 on both sides of the centrifugal impeller 2 can be changed simultaneously, that is, the inlet area and the outlet area of the centrifugal impeller 2 can be changed, so as to realize the adjustment of the inlet air flow rate under the condition that the rotational speed of the centrifugal compressor remains unchanged.

[0035] Preferably, the widths L of the impeller inlets 5 on both sides of the centrifugal impeller 2 and the widths L5 of the impeller outlets 6 are consistent. In this embodiment, the widths L of the impeller inlets 5 and the widths L5 of the impeller outlets 6 are consistent, which can ensure that the inlet air volume and the outlet air volume are consistent, making the gas flow in and out smoothly, and avoiding the retention and accumulation of air flow in the annular groove 34. At the same time, when adjusted to the preset minimum gas flow rate, the openings of the impeller inlet 5 and the impeller outlet 6 always remain consistent, jointly preventing excess gas from flowing into the intake casing 4 through the centrifugal impeller 2, and ensuring a stable and reliable minimum gas flow rate.

[0036] As Figure 3 and Figure 6 shown, the air collecting chamber 1 is an integral structure, with a partition 11 provided in the middle. The midline of the partition 11 is in the same plane as the axis of the centrifugal impeller 2. The gases discharged from the impeller outlets 6 on the left and right sides of the centrifugal impeller 2 flow into both sides of the partition 11 of the air collecting chamber 1 respectively, ensuring that the gases on both sides do not interfere with each other. The air collecting chamber is single-sided exhaust. After collecting the air flows at various circumferential positions of the impeller outlet, it converges to one side above and is discharged along the exhaust port above.

[0037] Preferably, the partition 11 is in the shape of an isosceles trapezoid. Among them, the width of the end of the partition 11 facing the centrifugal impeller 2 is smaller than the width of the end away from the centrifugal impeller 2.

[0038] Preferably, there is a certain gap between the end of the partition 11 facing the centrifugal impeller 2 and the tip of the centrifugal impeller 2 to ensure that there is no rubbing between the rotating and stationary parts.

[0039] Define L / L2 as the opening degree of the impeller shroud 3. Then, the power consumed by the centrifugal compressor will also show a certain variation law with the opening degree of the impeller shroud 3 (see Figure 7 ). At the same time, the flow rate of the centrifugal compressor will show a certain variation law with the change of the opening degree of the impeller shroud 3 (see Figure 8 ).

[0040] Preferably, when the two impeller shrouds 3 move along the rotation axis of the centrifugal impeller 2 to adjust the width L of the impeller inlet 5 and the width L5 of the impeller outlet 6, so that the centrifugal impeller 2 is opened from the minimum flow rate state (see Figure 9 ) to the maximum flow rate state (see Figure 10 ), the displacement distance of the impeller shroud is equal to the height L2 of the blade 22. In this embodiment, at a certain fixed rotational speed, the displacement distance is 30 mm. Therefore, the distance to be adjusted in this embodiment is very short, and generally, a displacement actuator can achieve a rapid adjustment of this displacement magnitude, thus meeting the requirements of high response speed adjustment.

[0041] Through the above design of the centrifugal impeller 2, impeller shroud 3, inlet casing 4, and gas collector 1 and the design of the key dimensions, a double-sided inlet centrifugal compressor with adjustable inlet air flow rate can be obtained.

[0042] An embodiment of another aspect of the present application further provides an aeroengine, including the double-sided inlet centrifugal compressor with adjustable inlet air flow rate described above.

[0043] The above are only the preferred embodiments of the present application and are not used to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A double-sided intake centrifugal compressor with adjustable intake air flow, characterized in that, it includes a centrifugal impeller (2), a gas collecting chamber (1), two impeller casings (3), two intake casings (4), and a displacement actuating mechanism. The centrifugal impeller (2) is a double-sided centrifugal impeller, including a hub (21) and blades (22) arranged back-to-back on both sides of the hub (21). The blades (22) are radial blades. The two impeller casings (3) are coaxially arranged with the centrifugal impeller (2) and symmetrically arranged on both sides of the centrifugal impeller (2) so as to be movable left and right along the rotation axis of the centrifugal impeller (2). On one side of each impeller casing (3) facing the blades (22), an annular groove (34) for accommodating the blades (22) is provided. An impeller intake port (5) is formed between the inner annular wall (32) on the side close to the center of the annular groove (34) and the hub (21) of the centrifugal impeller (2). An impeller outlet port (6) is formed between the outer annular wall (31) on the side far from the center of the annular groove (34) and the hub (21) of the centrifugal impeller (2). The two intake casings (4) are symmetrically arranged on both sides of the centrifugal impeller (2) and are connected to the impeller intake port (5) to provide intake air for the centrifugal impeller (2). The gas collecting chamber (1) is connected to the impeller outlet port (6) and is used for collecting the air flow from all circumferential parts of the impeller outlet port (6), converging it to one side and then discharging it along the exhaust port. The displacement actuating mechanism is respectively drivingly connected to the two impeller casings (3) and is used to drive the impeller casings (3) on both sides of the centrifugal impeller (2) to move left and right along the rotation axis of the centrifugal impeller (2), adjust the width L of the impeller intake port (5) on both sides of the centrifugal impeller (2) and the width L5 of the impeller outlet port (6), change the intake area and outlet area of the centrifugal impeller (2), and realize the adjustment of the intake air flow under the condition of constant rotational speed of the centrifugal compressor.

2. The double-sided intake centrifugal compressor with adjustable intake air flow according to claim 1, characterized in that, the width L3 of the outlet of the intake casing (4) is greater than the height L2 of the blades (22) of the centrifugal impeller (2).

3. The double-sided intake centrifugal compressor with adjustable intake air flow according to claim 2, characterized in that, the meridional projection of the inner surface of the impeller casing (3) is trapezoidal. Among them, the depth L4 of the inner annular wall (32) from the bottom of the annular groove (33) is 1.2 to 2 times the height L2 of the blades (22), and the depth L6 of the outer annular wall (31) from the bottom of the annular groove (33) is adjusted according to the slope of the hub (21) of the centrifugal impeller (2).

4. The double-sided intake centrifugal compressor with adjustable intake air flow according to claim 3, characterized in that, the depth L6 of the outer annular wall (31) from the bottom of the annular groove (33) is greater than or equal to the depth L4 of the inner annular wall (32) from the bottom of the annular groove (33).

5. The double-sided intake centrifugal compressor with adjustable intake air flow according to claim 4, characterized in that, the width L of the impeller intake port (5) on both sides of the centrifugal impeller (2) is consistent with the width L5 of the impeller outlet port (6).

6. The double-sided intake centrifugal compressor with adjustable intake air flow according to any one of claims 1 to 5, characterized in that, when the two impeller housings (3) move along the rotation axis of the centrifugal impeller (2) to adjust the width L of the impeller intake port (5) and the width L5 of the impeller outlet port (6), so that the centrifugal impeller (2) is opened from the minimum flow state to the maximum flow state, the displacement distance of the impeller housing is equal to the height L2 of the blade (22).

7. The double-sided intake centrifugal compressor with adjustable intake air flow according to claim 1, characterized in that, the air collecting chamber (1) is of an integral structure, and a partition plate (11) is arranged in the middle. The center line of the partition plate (11) and the axis of the centrifugal impeller (2) are in the same plane. The gases discharged from the impeller outlet ports (6) on the left and right sides of the centrifugal impeller (2) flow into both sides of the partition plate (11) of the air collecting chamber (1) respectively.

8. The double-sided intake centrifugal compressor with adjustable intake air flow according to claim 7, characterized in that, the partition plate (11) is in an isosceles trapezoid shape, wherein the width of the end of the partition plate (11) facing the centrifugal impeller (2) is smaller than the width of the end far from the centrifugal impeller (2).

9. The double-sided intake centrifugal compressor with adjustable intake air flow according to claim 7 or 8, characterized in that, there is a certain gap between the end of the partition plate (11) facing the centrifugal impeller (2) and the blade top of the centrifugal impeller (2).

10. An aeroengine, characterized in that, it includes the double-sided intake centrifugal compressor with adjustable intake air flow according to any one of claims 1 to 9.

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