Particle separator experimental apparatus with adjustable deflection angle of the flow divider

Abstract

This invention provides a particle separator experimental apparatus that allows for adjustment of the deflection angle of the flow divider. [Solution] The particle separator comprises a main passage adapter segment 11, a main passage total pressure probe 12, a bypass passage adapter segment, a bypass passage total pressure probe 15, and a low-pressure suction table 17. The particle separator draws in air from the atmospheric environment, and its terminal outlet is connected to a low-pressure gas source via a valve. During the experiment, the flow rate can be adjusted to various levels required for the experiment by adjusting the opening of a ball valve located downstream of the experimental table, and different operating modes of the particle separator can be switched by adjusting the rotation angle of the flow divider according to different inflow environments.

Description

Technical Field

[0001] The present invention relates to the field of air intake devices for turboshaft engines, and in particular to the field of integrated inertial particle separators.

Background Art

[0002] A sand-dust environment is a type of gas-solid two-phase flow environment formed by combining air with solid particles such as sand and dust, for example, it refers to areas such as deserts, sandy beaches and volcanic eruption sites, or weather conditions such as sandstorms caused by sand and dust carried by atmospheric movement. Due to the flight performance characteristics of helicopters, helicopters are usually operated in low-altitude, low-speed modes, and need to take off and land in simple sites and even random outdoor locations. When used in deserts and wastelands with scarce surface vegetation, and dry environments with exposed soil, under the action of surface wind and rotor downwash, quartz particles on the ground are lifted to varying degrees by airflow and suspended in the air, forming a high-concentration sand-dust cloud that envelops the aircraft in a short time, resulting in a brownout environment. Since the inhalation of sand and dust particles greatly affects the performance and service life of helicopter turboshaft engines, sand protection design for helicopter turboshaft engines is extremely important. In response to this demand, various sand and dust protection devices for turboshaft engines have been designed, such as vortex tube particle separators, intake-blocking filters and integrated inertial particle separators. Among these devices, inertial particle separators are widely used especially in high-speed helicopters and tiltrotor aircraft due to their light weight and low resistance.

[0003] Conventional inertial particle separators employ a fixed structure, meaning they are always operational upon installation. Furthermore, to ensure separation effectiveness, they often require the use of flow paths with greater curvature to create rotational vortices or radial momentum, resulting in significant aerodynamic losses. However, once a helicopter takes off and reaches a certain altitude, it no longer encounters a dusty environment, and engine power is wasted due to intake losses. Therefore, a particle separator is needed to resolve this contradiction and provide a reliable intake system for future high-speed helicopters. Additionally, a corresponding experimental apparatus needs to be designed to verify the feasibility of the particle separator scheme. At the same time, this experimental apparatus should be as simple in structure as possible and easy to operate and maintain. [Overview of the project] [Problems that the invention aims to solve]

[0004] To solve the above problems, the present invention provides a particle separator experimental apparatus with an adjustable deflection angle of the flow divider, which has a simple structure, small dimensions, lower requirements for experimental location and gas supply capacity, and is easy to operate and maintain. [Means for solving the problem]

[0005] To achieve the above objectives, the technical solutions employed by the present invention are as follows.

[0006] A particle separator experimental apparatus with adjustable deflection angle of the shunt, comprising a particle separator, a main passage adapter segment, a main passage total pressure probe, a bypass passage adapter segment, a bypass passage total pressure probe, and a low-pressure suction table, wherein the particle separator includes a housing, a flow straightening lip located at the front of the housing, a rotatable shunt, a shunt fixing segment, a shunt push rod, and a drive unit, wherein the shunt fixing segment is fixed within the housing, the end of the rotatable shunt is hinged to the front of the shunt fixing segment, the drive unit is located near the outside of the housing, the end of the shunt push rod is connected to the drive unit, and the tip of the shunt push rod is inserted into the housing and located outside the rotatable shunt. The shunt push rod is provided with a slide groove, and the rotatable shunt is provided with a slide shaft that is inserted into the slide groove and slides within the slide groove. The drive device drives the shunt push rod forward or backward, causing the tip of the rotatable shunt to swing around the hinge connection point between the rotatable shunt and the shunt fixed segment as its axis. The shunt fixed segment divides the housing outlet into two within the housing, with one outlet communicating with one end of the main passage adapter segment and the other outlet communicating with one end of the bypass passage adapter segment. The other end of the main passage adapter segment communicates with the main passage total pressure probe, and the other end of the bypass passage adapter segment communicates with the bypass passage total pressure probe.

[0007] Furthermore, by positioning the particle separator perpendicular to the ground, the influence of gravity on sand separation efficiency is avoided.

[0008] Furthermore, it further includes a main passage dust collection bucket connected to the main passage total pressure probe, and a bypass passage dust collection bucket connected to the bypass passage total pressure probe.

[0009] Furthermore, the ratio of the inlet area to the outlet area of ​​the main passage adapter segment is 1:1, and the ratio of the width to the height at the inlet of the particle separator is 2:1.

[0010] Furthermore, rounding the lower wall of the particle separator, the rotatable flow divider, the fixed segment of the flow divider, and both sides of the upper wall of the particle separator helps to avoid the influence of angular vortices on the flow field of the particle separator.

[0011] Furthermore, the rotation angle range of the rotatable shunt is from -12° counterclockwise to 26° clockwise.

[0012] Furthermore, the ratio of the inlet area to the outlet area of ​​the bypass passage adapter segment is 1:1.169.

[0013] Furthermore, the drive device is a stepping motor, the output shaft of the stepping motor is a screw, and the end of the shunt push rod is provided with a female threaded sleeve that fits onto the head of the screw, and the tip of the shunt push rod is inserted into the housing so that the shunt push rod can only move forward or backward, and the screw and the female threaded sleeve form a screw transmission mechanism.

[0014] Furthermore, the side walls of the particle separator are made of transparent acrylic.

[0015] Furthermore, 18 static pressure holes are provided on both the upper and lower walls of the particle separator, with the spacing between adjacent static pressure holes being 5% of the wall cross-sectional curve length. [Effects of the Invention]

[0016] Compared to conventional inertial particle separators, the particle separator according to the present invention can change its mold surface according to different flight environments and switch between different operating modes. When encountering harsh sandy environments or during hovering, it switches to a high separation efficiency mode, significantly improving the sand separation efficiency of the particle separator compared to the standard mode. When high-speed cruising is required, it switches to a low flow loss mode, reducing total pressure loss and decreasing strain index. The particle separator provides an efficient intake protection device for future high-speed helicopter power units (e.g., axial flow fan engines). Furthermore, the particle separator experimental apparatus according to the present invention can simulate the aerodynamic performance and sand separation performance of the particle separator under different mainstream Mach numbers and different scavenging ratios, providing a practical experimental apparatus for research verifying the aerodynamic performance and sand separation performance of particle separators. [Brief explanation of the drawing]

[0017] [Figure 1] This is a schematic diagram of a particle separator experimental apparatus according to the present invention, in which the deflection angle of the diverter can be adjusted. [Figure 2] This is the corresponding mode of the particle separator according to the present invention. [Figure 3] This is a schematic diagram of the angle between the rotatable flow divider and the fixed flow divider segment in the present invention. [Figure 4] This is a diagram showing the internal structure of a particle separator. [Figure 5] This diagram shows the flow divider adjustment mechanism of a particle separator. [Figure 6] This diagram compares the sand separation efficiency during hovering in the standard mode and the high-efficiency separation mode of the particle separator. [Figure 7] This is a comparison chart of the total pressure recovery coefficient during cruising in the reference mode and low flow loss mode of the particle separator. [Figure 8] This is a comparison chart of the DC60 during cruising in the reference mode and low flow loss mode of the particle separator. [Figure 9] This is a schematic diagram of the drive mechanism. [Modes for carrying out the invention]

[0018] Disclosed is a particle separator experimental device with an adjustable deflection angle of a flow divider, comprising a particle separator, a main passage adapter segment 11, a main passage total pressure probe 12, a bypass passage adapter segment 14, a bypass passage total pressure probe 15, a low-pressure suction table 17, a main passage dust collection bucket 13 connected to the main passage total pressure probe 12, and a bypass passage dust collection bucket 16 connected to the bypass passage total pressure probe 15. The low-pressure suction table 17 communicates with the main passage dust collection bucket 13 and the bypass passage dust collection bucket 16 respectively via pipes.

[0019] The particle separator comprises a housing, a straightening lip 1 located at the front end of the housing, a rotatable flow divider 9, a flow divider fixing segment 10, a flow divider push rod 4, and a driving device 7.

[0020] The flow divider fixing segment 10 is fixed inside the housing, the tail end of the rotatable flow divider 9 is hinged to the front end of the flow divider fixing segment 10, the driving device 7 is located near the outer side of the housing, the tail end of the flow divider push rod 4 is connected to the driving device 7, the front end of the flow divider push rod 4 is inserted into the housing and located on the outer side of the rotatable flow divider 9, a slide groove 41 is provided on the flow divider push rod 4, a slide shaft 91 inserted into the slide groove and slidable in the slide groove is provided on the rotatable flow divider 9, the driving device drives the flow divider push rod 4 to move forward or backward, thereby driving the front end of the rotatable flow divider 9 to swing with the hinged connection between the rotatable flow divider 9 and the flow divider fixing segment 10 as the axis.

[0021] The flow divider fixing segment 10 divides the housing outlet into two parts in the housing, one outlet communicates with one end of the main passage adapter segment 11, and the other outlet communicates with one end of the bypass passage adapter segment 14. The other end of the main passage adapter segment 11 communicates with the main passage total pressure probe 12, and the other end of the bypass passage adapter segment 14 communicates with the bypass passage total pressure probe 15. As shown in Fig. 9, the driving device is a stepping motor 7, the output shaft of the stepping motor 7 is a screw 71, and the end of the flow divider push rod 4 is provided with an internal thread sleeve 72 fitted to the head of the screw 71. The front end of the flow divider push rod 4 is inserted into the housing, so that the flow divider push rod 4 can only move forward or backward, and the screw 71 and the internal thread sleeve 72 form a screw transmission mechanism.

[0022] The following describes the detailed procedure for implementing an experimental apparatus designed using the method of the present invention, with a main stream outlet Mach number of 0.1 to 0.5 and a scavenging ratio of 5% to 60%. As shown in Figures 1 to 5, the upstream stage of the particle separator shunt can rotate around the rotation center of the downstream stage of the shunt, and by changing different angles to switch between different operating modes, it can adapt to different flight conditions. Refer to Figure 1 for the shape of the shunt in different operating modes, and Figure 2(b) shows the reference mode, in which case the angle α between the rotatable shunt 9 and the shunt fixed segment 10 is 4°. As shown in Figure 3, the angle α is the angle between the central axis of the rotatable shunt 9 and the central axis of the shunt fixed segment 10. In this embodiment, since the rotatable shunt 9 has an asymmetric structure, the central axis of the rotatable shunt 9 is defined as the line connecting the hinge connection point 19 between the end of the rotatable shunt 9 and the tip of the shunt fixed segment 10 and the axis of the slide shaft 91. This mode is applied to normal flight conditions, such as low-speed forward flight and flight conditions where dust concentration is not high. In this mode, aerodynamic performance is good and sand separation performance is within acceptable limits. Figure 2(a) shows the high separation efficiency mode, which is switched by rotating the shunt counterclockwise by 4° from the reference mode. This mode is applied to flight conditions where dust concentration in the environment is high. In this mode, the sand separation performance of the particle separator is significantly improved compared to the reference mode, but the aerodynamic performance is slightly reduced. Figure 2(c) shows the low flow loss mode, which is switched by rotating the shunt clockwise by 16° from the reference mode. This mode is applied during high-speed cruising. In this mode, the aerodynamic performance of the particle separator is significantly improved compared to the reference mode.Based on the above, the particle separator mold surface is designed with a corresponding experimental apparatus. The laboratory bench has piping from one inlet to two outlets (main passage / bypass passage). From the inlet to the outlet of the laboratory bench, in order, are the flow straightening lip 1, observation side wall 2, lower wall surface of the particle separator 3, flow divider push rod 4, particle separator bracket 5, motor base 6, stepping motor 7, upper wall surface of the particle separator 8, rotatable flow divider 9, flow divider fixed segment 10, main passage adapter segment 11, main passage total pressure probe 12, main passage dust collection bucket 13, bypass passage adapter segment 14, bypass passage total pressure probe 15, bypass passage dust collection bucket 16, and low-pressure suction table 17.

[0023] The rectifying lip 1, main passage adapter segment 11, and bypass passage adapter segment 14 are 3D printed, integrated components that reduce the number of connecting members and mitigate interference with the downstream flow field. The particle separator body consists of an observation side wall 2, a lower wall surface 3 of the particle separator, a rotatable flow divider 9, a flow divider fixing segment 10, and an upper wall surface 8 of the particle separator.

[0024] To monitor the flow rate and aerodynamic performance of the main bypass passage, a total pressure probe is connected downstream of the particle separator body, and each total pressure probe is connected to the main bypass passage via an adapter segment.

[0025] To monitor the flow field structure within the piping of the experimental bench, static pressure holes 18 are designed on the upper and lower walls of the particle separator body for attaching static pressure probes. Due to differences in the laws governing the change of flow field parameters at different locations, the spacing of the static pressure holes varies depending on the location. There are 18 static pressure holes 18 on both the upper and lower walls, with a spacing of 5% of the wall cross-sectional curve length. Furthermore, to facilitate the study of the trajectory of dust particles within the particle separator, the side walls (2 / 2′) are made of transparent acrylic and can be used to observe the motion characteristics of dust particles within the particle separator during the experimental process.

[0026] To meet the requirements of the downstream engine, square-to-circular adapter segments are connected to the outlets of the main and bypass passages of the particle separator, respectively. The ratio of the inlet area to the outlet area of ​​the main passage adapter segment is 1:1, and the ratio of the inlet area to the outlet area of ​​the bypass passage adapter segment is 1:1.169. The law governing the change in the centerlines of these mold surfaces is that the speed of change is moderate, thereby reducing flow losses due to changes in the mold surface. The lower wall surface 3 of the particle separator, the upper wall surface 8 of the particle separator, the rotatable flow divider 9, and the fixed flow divider segment 10 are all rounded on both sides to reduce the effect of angular vortices on the flow.

[0027] The deflection angle adjustment method for the flow deflector of the particle separator may also be shown in Figures 4 and 5. The lower wall of the particle separator is connected to the motor base 6 via the particle separator bracket 5. A stepping motor 7 is mounted on the motor base 6. The screw of the stepping motor 7 is connected to the flow deflector push rod by a thread. The operation of the stepping motor 7 drives the flow deflector push rod 4 up and down. The upper part of the flow deflector push rod 4 is connected to a rotatable flow deflector 9. The rear end of the rotatable flow deflector 9 is connected to the tip of the flow deflector fixed segment 10. Thus, the rotatable flow deflector 9 can rotate around the tip of the flow deflector fixed segment 10 as the center of rotation. The up and down movement of the flow deflector push rod rotates the flow deflector, thereby making the flow deflector adjustable and switching between different operating modes of the particle separator.

[0028] In this invention, the effectiveness of the above technical solution was verified by employing a numerical simulation method, simulating the aerodynamic performance and sand separation performance in different operating modes under different flight conditions. Figure 6 shows a comparison of the AC fine sand separation efficiency of the reference mode and the high separation efficiency mode under different scavenging ratio conditions during hovering, confirming that the sand and dust separation performance of the high separation efficiency mode is superior to that of the reference mode under the same scavenging ratio conditions. Figures 7 and 8 show a comparison of the aerodynamic performance of the reference mode and the low flow loss mode during high-speed cruising, confirming that after switching to the low flow loss mode, the total pressure loss of the particle separator decreases, the strain index decreases, and the aerodynamic performance improves, thus proving the feasibility of the particle separator scheme.

[0029] Furthermore, there are many specific methods and pathways for realizing the present invention, and the above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various further improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered to fall within the scope of protection of the present invention.

Claims

1. A particle separator experimental apparatus with an adjustable deflection angle for the flow divider, The system comprises a particle separator, a main passage adapter segment (11), a main passage total pressure probe (12), a bypass passage adapter segment (14), a bypass passage total pressure probe (15), and a low-pressure suction table (17). The particle separator includes a housing, a flow straightening lip (1) located at the front of the housing, a rotatable flow divider (9), a flow divider fixing segment (10), a flow divider push rod (4), and a drive unit (7). The shunt fixed segment (10) is fixed within the housing, the end of the rotatable shunt (9) is hinged to the tip of the shunt fixed segment (10), the drive unit (7) is located near the outside of the housing, the end of the shunt push rod (4) is connected to the drive unit (7), the tip of the shunt push rod (4) is inserted into the housing and located outside the rotatable shunt (9), the shunt push rod (4) is provided with a slide groove (41), the rotatable shunt (9) is provided with a slide shaft (91) that is inserted into the slide groove and slides within the slide groove, the drive unit drives the shunt push rod (4) forward or backward, causing the tip of the rotatable shunt (9) to swing around the hinged connection point between the rotatable shunt (9) and the shunt fixed segment (10) as the axis. The shunt fixed segment (10) divides the housing outlet into two within the housing, with one outlet communicating with one end of the main passage adapter segment (11) and the other outlet communicating with one end of the bypass passage adapter segment (14). The other end of the main passage adapter segment (11) communicates with the main passage total pressure probe (12), and the other end of the bypass passage adapter segment (14) communicates with the bypass passage total pressure probe (15). The system further comprises a main passage dust collection bucket (13) connected to a main passage total pressure probe (12), and a bypass passage dust collection bucket (16) connected to a bypass passage total pressure probe (15), A particle separator experimental apparatus with adjustable deflection angle of the flow divider, characterized in that the low-pressure suction table (17) is connected via piping to a main passage dust collection bucket (13) and a bypass passage dust collection bucket (16), respectively.

2. The particle separator experimental apparatus according to claim 1, characterized in that the particle separator is placed perpendicular to the ground, thereby avoiding the effect of gravity on the sand separation efficiency.

3. The particle separator experimental apparatus according to claim 1, characterized in that the ratio of the inlet area to the outlet area of ​​the main passage adapter segment (11) is 1:1, and the ratio of the width to the height at the inlet of the particle separator is 2:

1.

4. The particle separator experimental apparatus according to claim 1, characterized in that the lower wall surface (3) of the particle separator, the rotatable flow divider (9), the flow divider fixing segment (10), and both sides of the upper wall surface (8) of the particle separator are rounded to avoid the influence of angular vortices on the flow field of the particle separator.

5. The particle separator experimental apparatus according to claim 1, characterized in that the rotation angle range of the rotatable flow divider (9) is from -12° counterclockwise to 26° clockwise.

6. The particle separator experimental apparatus according to claim 1, characterized in that the ratio of the inlet area to the outlet area of ​​the bypass passage adapter segment (14) is 1:1.

169.

7. The particle separator experimental apparatus according to claim 1, characterized in that the drive device is a stepping motor (7), the output shaft of the stepping motor (7) is a screw (71), the end of the shunt push rod (4) is provided with a female threaded sleeve (72) that fits onto the head of the screw (71), and the tip of the shunt push rod (4) is inserted into the housing so that the shunt push rod (4) can only move forward or backward, and the screw (71) and the female threaded sleeve (72) form a screw transmission mechanism.

8. The particle separator experimental apparatus according to claim 1, characterized in that the side wall (2) of the particle separator is made of a transparent acrylic plate.

9. The particle separator experimental apparatus according to claim 1, characterized in that 18 static pressure holes (18) are provided on the upper wall surface and the lower wall surface of the particle separator, and the spacing between adjacent static pressure holes is 5% of the wall cross-sectional curve length.

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