Turbine guide structure, turbine, and air cycle machine

Abstract

The present invention provides a turbine flow guiding structure, a turbine, and an air cycle machine. The turbine flow guiding structure includes: a fixing plate, the fixing plate is annular, along the axial direction of the fixing plate, a plurality of blades are arranged on the fixing plate. One end of the blade faces the inner wall of the fixing plate, and the other end faces the outer wall of the fixing plate. The end point of the other end of the blade is the coordinate origin (0, 0). The direction from the coordinate origin (0, 0) to the center of the fixing plate is the X-axis. There is a connecting line between any point on the mid-arc of the blade and the coordinate origin. The included angle y1 between the connecting line and the X-axis satisfies: y1 = ax<supgt;4< / supgt> - bx<supgt;3< / supgt> + cx<supgt;2< / supgt> - dx + e; It can overcome the defect that the pressure fluctuation caused by the supersonic region in the prior art is applied to the surface of the guide vane, which is likely to cause fatigue spalling of the guide vane.

Description

Technical Field

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

[0002] In an aircraft air cycle machine, the centripetal turbine plays the role of a prime mover. The airflow expands inside the turbine and does work to drive the entire rotor system. Therefore, the aerodynamic performance of the turbine directly determines the quality of the air cycle machine.

[0003] As the upstream component of the turbine, the turbine guide vane can reduce the pressure and accelerate the incoming high-pressure air, allowing the high-speed airflow to enter the turbine rotor and drive it to do work. It can be seen that the flow state in the guide vane flow channel directly determines the performance of the downstream rotor; the two work together to make the air cycle machine reach a good working state.

[0004] However, since the flow area of ​​the guide vane gradually decreases along the flow direction, the air can easily be accelerated to a supersonic state at its outlet, causing the turbine blockage boundary to approach the design point; in addition, the pressure fluctuations caused by the supersonic zone are applied to the surface of the guide vane, which can easily cause fatigue peeling of the guide vane as the working time increases.

[0005] In the prior art, since the guide vane has a long arc length, a small head, and the maximum thickness is located in the rear half of the guide vane in the flow direction, the air has been accelerated to a supersonic state at the guide vane flow channel outlet, thereby generating shock waves, which seriously interfere with the boundary layer flow on the blade surface, affect the airflow state at the rotor inlet, and generate unnecessary shock wave losses. At this time, the turbine is close to the blockage point and the efficiency value is reduced. Summary of the invention

[0006] Therefore, the present invention provides a turbine guide structure, a turbine, and an air cycle machine, which can overcome the defect in the prior art that the pressure fluctuation caused by the supersonic region is applied to the surface of the guide vane, which easily causes fatigue peeling of the guide vane.

[0007] In order to solve the above problems, the present invention provides a turbine guide structure, which includes: a fixed plate, the fixed plate is annular, and a plurality of blades are arranged on the fixed plate along the axial direction of the fixed plate, one end of the blade is opposite to the inner wall of the fixed plate, and the other end is opposite to the outer wall of the fixed plate, and the other end of the blade is the coordinate origin (0, 0), the direction of the coordinate origin (0, 0) and the center of the fixed plate is the X-axis, and there is a connecting line between any point on the mid-arc line of the blade and the coordinate origin, and the angle y1 between the connecting line and the X-axis satisfies:

[0008] y1=ax 4 -bx 3 +cx 2-dx+e, wherein x is the relative value of any point on the mid-arc line of the blade on the X-axis, a=4.5-5, b=85-95, c=115-125, d=0.15-0.2, and e=40-50.

[0009] In some embodiments, a=4.7, b=90, c=120, d=0.17, and e=46.

[0010] In some embodiments, along the radial direction of the fixing plate, the greater the relative value of any point on the mid-arc line of the blade on the X-axis, the greater the value of the angle y1 first increases and then decreases.

[0011] In some embodiments, the width between the inner wall and the outer wall of the fixing plate is L, and when the relative value of any point on the mid-arc line of the blade on the X-axis is 90% to 100% L, the value of the angle y1 tends to decrease.

[0012] In some embodiments, the thickness y of the blade satisfies: y=fx 4 +gx 3 +hx 2 +jx+k, the thickness of the blade is applied symmetrically along both sides of the mid-arc line of the blade, f=25-30, g=45-50, h=5.5-6, j=10-15, k=1-1.5.

[0013] In some embodiments, f=29, g=49, h=5.8, j=14, k=1.3.

[0014] In some embodiments, along the radial direction of the fixing plate, the larger the relative value of any point on the mid-arc line of the blade on the X-axis is, the thickness of the blade increases first and then decreases.

[0015] In some embodiments, the width between the inner wall and the outer wall of the fixing plate is L, and when the relative value of any point on the mid-arc line of the blade on the X-axis is 40% to 50% of L, the thickness of the blade is maximum.

[0016] The present invention also provides a turbine, comprising the turbine flow guide structure as described in any of the preceding items.

[0017] The present invention also provides an air cycle machine, comprising the turbine as described in any one of the preceding items.

[0018] The present invention provides a turbine guide structure, a turbine, and an air cycle machine. By designing the distribution of the angle y1, the installation angle of the blade and the arc length of the blade are determined, so that the air loss along the way is reduced. The installation angle of the blade and the arc length of the blade are changed, so that the air loss along the way is reduced, the stability margin of the turbine is increased, and the aerodynamic performance of the turbine is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic structural diagram of a turbine flow guide structure according to an embodiment of the present invention;

[0020] Figure 2 A side view of a turbine guide structure according to an embodiment of the present invention;

[0021] Figure 3 A schematic diagram of the flow direction of a turbine flow guide structure according to an embodiment of the present invention;

[0022] Figure 4 Schematic diagram of the distribution of the angle between the connecting line and the X-axis in the turbine guide structure according to an embodiment of the present invention, wherein the horizontal axis is the relative value of any point on the mid-arc line of the blade on the X-axis, and the vertical axis is the degree of the angle;

[0023] Figure 5 Schematic diagram of the distribution of guide vanes of a turbine guide structure according to an embodiment of the present invention, wherein the horizontal axis is the relative value of any point on the mid-arc line of the blade on the X-axis, and the vertical axis is the thickness of the guide vane;

[0024] Figure 6 The supersonic state diagram of the prior art;

[0025] Figure 7 This is a subsonic state diagram of the turbine guide structure according to an embodiment of the present invention.

[0026] The reference numerals are:

[0027] 01. Blade; 02. Fixed plate. DETAILED DESCRIPTION

[0028] See also Figure 6 and Figure 7 As shown in the figure, in the prior art, the air at the guide vane outlet has reached a supersonic state (Mach number greater than 1), and the turbine is already in a blocked state. Figure 7 ) The Mach number at the guide vane outlet is about 0.84, which not only meets the requirements of the previous one-dimensional calculation, but also significantly delays the appearance of the guide vane outlet shock wave and increases the stability margin of the turbine. At the same time, the guide vane blade load is mainly located in the second half, which has a positive significance for weakening or even eliminating the supersonic zone at the guide vane outlet.

[0029] See also Figures 1 to 5As shown, an embodiment of the present invention provides a turbine guide structure, including: a fixed plate 02, the fixed plate 02 is annular, and along the axial direction of the fixed plate 02, a plurality of blades 01 are arranged on the fixed plate 02, one end of the blade 01 is opposite to the inner wall of the fixed plate 02, and the other end is opposite to the outer wall of the fixed plate 02, and the other end of the blade 01 is the coordinate origin (0, 0), and the direction between the coordinate origin (0, 0) and the center of the fixed plate 02 is the X axis (i.e. Figure 5 The flow direction in is the flow direction of air on the blade 01), there is a line between any point on the mid-arc line of the blade 01 and the coordinate origin, and the angle y1 between the line and the X-axis satisfies:

[0030] y1=ax 4 -bx 3 +cx 2 -dx+e, wherein x is the relative value of any point on the mid-arc line of the blade 01 on the X-axis, a=4.5-5, b=85-95, c=115-125, d=0.15-0.2, e=40-50. Preferably, a=4.7, b=90, c=120, d=0.17, e=46. In this technical solution, by designing the distribution of the angle y1, the installation angle of the blade 01 and the arc length of the blade 01 are determined, so that the air loss along the way is reduced, the installation angle of the blade 01 and the arc length of the blade 01 are changed, so that the air loss along the way is reduced, the stability margin of the turbine is increased, and the aerodynamic performance of the turbine is improved.

[0031] In some embodiments, along the radial direction of the fixing plate 02, the greater the relative value of any point on the mid-arc line of the blade 01 on the X-axis, the value of the angle y1 first increases and then decreases. Specifically, the width between the inner wall and the outer wall of the fixing plate 02 is L, and when the relative value of any point on the mid-arc line of the blade 01 on the X-axis is 90% to 100% L, the value of the angle y1 tends to decrease. In this technical solution, by limiting the relationship between the angle y1 and the relative value of any point on the mid-arc line of the blade 01 on the X-axis, the installation angle of the blade 01 and the arc length of the blade 01 are changed, so that the air loss along the way is reduced, the stability margin of the turbine is increased, and the aerodynamic performance of the turbine is improved.

[0032] In some embodiments, the thickness y of the blade 01 satisfies: y=fx 4 +gx 3 +hx 2+jx+k, in units of mm, the thickness of the blade 01 is applied symmetrically on both sides of the mid-arc line of the blade 01. f=25-30, g=45-50, h=5.5-6, j=10-15, k=1-1.5, preferably, f=29, g=49, h=5.8, j=14, k=1.3. In this technical solution, preferably, the head of the blade 01 is larger and can adapt to a larger range of incoming flow angles. The thickness of the blade 01 is applied symmetrically on both sides of the mid-arc line of the blade 01, that is, the thickness on one side of the mid-arc line of the blade 01 is y / 2. By changing the thickness distribution of the blade 01, the maximum thickness of the guide vane is increased, and the surface load distribution of the blade 01 is in a reasonable state, so that the outlet air is maintained in a subsonic state, ensuring that the turbine design point is maintained in a stable working state, widening the stability margin of the turbine, and improving the turbine aerodynamic performance.

[0033] In some embodiments, along the radial direction of the fixing plate 02, the greater the relative value of any point on the mid-arc line of the blade 01 on the X-axis, the greater the thickness of the blade 01 first increases and then decreases. The width between the inner wall and the outer wall of the fixing plate 02 is L, and when the relative value of any point on the mid-arc line of the blade 01 on the X-axis is 40% to 50% of L, the thickness of the blade 01 is the largest. In this technical solution, preferably, when the relative value of any point on the mid-arc line of the blade 01 on the X-axis is 45%L, the thickness of the blade 01 is the largest, the head of the blade 01 is larger, and it can adapt to a larger range of incoming flow angles. The thickness of the blade 01 is applied symmetrically on both sides of the mid-arc line of the blade 01, that is, the thickness on one side of the mid-arc line of the blade 01 is y / 2. By changing the thickness distribution of the blade 01, the maximum thickness of the guide vane is increased, and the surface load distribution of the blade 01 is in a reasonable state, so that the outlet air is maintained in a subsonic state, ensuring that the turbine design point is maintained in a stable working state, widening the stability margin of the turbine, and improving the aerodynamic performance of the turbine.

[0034] The present invention also provides a turbine, comprising the turbine flow guide structure as described in any of the preceding items.

[0035] The present invention also provides an air cycle machine, comprising the turbine mentioned above.

[0036] 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. A turbine flow guide structure, characterized in that: include: A fixed plate (02), the fixed plate (02) is annular, and along the axial direction of the fixed plate (02), a plurality of blades (01) are arranged on the fixed plate (02), one end of the blade (01) is opposite to the inner wall of the fixed plate (02), and the other end is opposite to the outer wall of the fixed plate (02), the other end of the blade (01) is a coordinate origin (0, 0), the direction of the coordinate origin (0, 0) and the center of the fixed plate (02) is an X-axis, there is a connecting line between any point on the mid-arc line of the blade (01) and the coordinate origin, and the angle y1 between the connecting line and the X-axis satisfies: y1=ax 4 -bx 3 +cx 2 -dx+e, wherein x is the relative value of any point on the mid-arc line of the blade (01) on the X-axis, a=4.5-5, b=85-95, c=115-125, d=0.15-0.2, and e=40-50.

2. The turbine flow guide structure according to claim 1, characterized in that: a=4.7, b=90, c=120, d=0.17, e=46.

3. The turbine flow guide structure according to claim 1, characterized in that: Along the radial direction of the fixing plate (02), the greater the relative value of any point on the mid-arc line of the blade (01) on the X-axis, the greater the value of the angle y1 first increases and then decreases.

4. The turbine flow guide structure according to claim 1, characterized in that: The width between the inner wall and the outer wall of the fixing plate (02) is L, and when the relative value of any point on the mid-arc line of the blade (01) on the X-axis is 90% to 100% L, the value of the angle y1 tends to decrease.

5. The turbine flow guide structure according to claim 1, characterized in that: The thickness y of the blade (01) satisfies: y=fx 4 +gx 3 +hx 2 +jx+k, the thickness of the blade (01) is applied symmetrically along the two sides of the mid-arc line of the blade (01), f=25-30, g=45-50, h=5.5-6, j=10-15, k=1-1.

5.

6. The turbine flow guide structure according to claim 5, characterized in that: f=29, g=49, h=5.8, j=14, k=1.

3.

7. The turbine flow guide structure according to claim 5, characterized in that: Along the radial direction of the fixing plate (02), the greater the relative value of any point on the mid-arc line of the blade (01) on the X-axis, the thickness of the blade (01) first increases and then decreases.

8. The turbine flow guide structure according to claim 5, characterized in that: The width between the inner wall and the outer wall of the fixing plate (02) is L, and when the relative value of any point on the mid-arc line of the blade (01) on the X-axis is 40% to 50% of L, the thickness of the blade (01) is maximum.

9. A turbine, characterized in that: The invention comprises the turbine flow guide structure according to any one of claims 1 to 8.

10. An air cycle machine, characterized in that: A turbine comprising the turbine of claim 9.

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