A dual-channel experimental device for constructing compressor inlet flow field

Abstract

The invention discloses a dual-channel experimental device for constructing a compressor inlet flow field, the dual-channel experimental device comprises a bell mouth section, a circular sleeve tube section, an airflow construction section and an experimental section connected in sequence, the lower end of the circular sleeve tube section casing is fastened to the bell mouth section casing by an external connection method of bolts and nuts evenly arranged in the circumference of a flange, the upper end of the circular sleeve tube section casing is fastened to the lower end of the airflow construction section casing by an external connection method of bolts and nuts evenly arranged in the circumference of a flange, and the upper end of the airflow construction section casing is fastened to the lower end of the experimental section casing by an external connection method of bolts and nuts evenly arranged in the circumference of a flange. The device can divide the wind tunnel flow into an inner channel flow field and an outer channel flow field, providing the possibility of constructing a small-diameter-height ratio compressor inlet, and the device has a simple structure and is easy to process, ensuring that the experimental device can be installed, disassembled and maintained conveniently and quickly.

Description

Technical Field

[0001] The invention relates to an annular blade grid experimental device, in particular to a double-channel experimental device for constructing a compressor inlet flow field. Background Art

[0002] In aircraft engines and aero-derivative gas turbines, due to the small diameter-to-height ratio of the fan and low-pressure compressor blades at the compressor inlet, the circumferential speed difference between the root and the blade tip is large, resulting in the radial distribution of parameters such as the airflow Mach number and total pressure. In order to conduct experimental research on small diameter-to-height ratio compressor blades when the test piece is stationary, it is extremely necessary to use experimental equipment to construct the compressor blade inlet flow.

[0003] At present, in order to achieve the above-mentioned inlet flow conditions, the method of installing a guide vane with a smaller twist angle or a straight blade guide vane in front of the test piece is usually adopted to increase the velocity gradient between the tip and the root of the inlet of the test piece. The effect of this single-channel design method is not ideal, because the small twist angle of the guide vane can easily cause the instability of the radial pressure of the fluid to produce additional mixing losses, affecting the stability of the wind tunnel flow field. The use of a multi-channel inlet can reduce the impact of the above defects and increase the adjustability of different flow channel flow structures by dividing the flow channel. However, the multi-channel in the prior art mainly has the following problems: using a multi-channel design, too many channels lead to an increase in the number of parts of the test piece, increase the difficulty of processing, and complicate the assembly process, further increasing the wind tunnel test time and reducing the efficiency of the wind tunnel test. Summary of the invention

[0004] In view of the defects of the existing experimental technology, the present invention provides a dual-channel experimental device for constructing the compressor inlet flow field. The device can divide the wind tunnel flow into the inner channel flow field and the outer channel flow field, providing the possibility of constructing a small-diameter-height ratio compressor inlet, and the device has a simple structure and is easy to process, ensuring that the experimental device can be installed, disassembled and maintained conveniently and quickly.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] A dual-channel experimental device for constructing a compressor inlet flow field comprises a bell mouth section, a circular sleeve section, an airflow construction section and an experimental section which are connected in sequence, wherein:

[0007] The bell mouth section includes a bell mouth section casing;

[0008] The circular sleeve tube section comprises a circular sleeve tube section casing, and inner and outer channel partitions, an inner channel rectifying cone and inner and outer channel guide plates arranged inside the circular sleeve tube section casing;

[0009] The airflow construction section comprises an airflow construction section casing and a mandrel arranged inside the airflow construction section casing;

[0010] The experimental section includes an experimental section casing, and experimental section blades and an experimental section rectifying cone arranged inside the experimental section casing;

[0011] The lower end of the circular sleeve tube section casing is fastened to the bell mouth section casing by an external connection method of bolts and nuts evenly arranged in the circumference of the flange, the upper end of the circular sleeve tube section casing is fastened to the lower end of the airflow structure section casing by an external connection method of bolts and nuts evenly arranged in the circumference of the flange, and the upper end of the airflow structure section casing is fastened to the lower end of the test section casing by an external connection method of bolts and nuts evenly arranged in the circumference of the flange;

[0012] The inner and outer channel partitions and the inner channel rectifying cone are evenly distributed with a plurality of guide plate grooves along the circumferential direction, and the inner and outer channel guide plates are connected to the circular sleeve pipe section casing by sequentially passing through the inner channel rectifying cone and the guide plate grooves on the inner and outer channel partitions from the inside of the inner channel rectifying cone;

[0013] The inner and outer channel partitions extend from the inlet of the circular sleeve tube section to the outlet of the airflow construction section, dividing the flow channel of the airflow construction section into an inner channel flow channel and an outer channel flow channel;

[0014] The inlet and outlet of the airflow structure section casing are each provided with a row of reserved holes. The reserved holes at the inlet are used to install turbine blades, compressor blades or vortex screens for the construction of the total pressure and velocity of the flow field, and the reserved holes at the outlet are used to install spoiler rods or adjustable guide vanes for the simulation of incoming flow wake and the adjustment of the inlet airflow angle.

[0015] The outer wall of the experimental section straightening cone is provided with a plurality of experimental section blades evenly distributed along the circumferential direction, and a transmission shaft fixing seat is provided at the front end of the experimental section straightening cone;

[0016] The two ends of the mandrel are respectively connected to the inner channel rectifying cone and the experimental section transmission shaft fixing seat.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. The bell mouth adopts the Vickers curve design, which ensures the acceleration of the inlet of the experimental device while obtaining better airflow quality;

[0019] 2. The inlet flow field of the experimental piece is divided into an inner channel flow channel and an outer channel flow channel by the inner and outer channel partitions of the circular sleeve pipe section, so that a flow regulating device can be installed in the airflow structure section according to the experimental requirements to construct the flow field required for the experiment;

[0020] 3. The bell mouth section, the coaxially mounted circular sleeve section, the airflow structure section and the casing and the shaft of the experimental section are connected by fixed bolts, which ensures the stability of the experimental device structure and the convenience of disassembly, assembly and replacement;

[0021] 4. The transmission shaft fixing seat in front of the rectifier cone of the experimental section can fix the transmission shaft. If the inner channel is equipped with adjustable guide vanes, the transmission shaft can be connected to the inner channel adjustable guide vanes to adjust the installation angle of the inner channel adjustable guide vanes;

[0022] 5. The casing and shaft of each structure are connected with fixed bolts to ensure easy disassembly, assembly and processing of the experimental parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the longitudinal section diagram of the dual-channel experimental device;

[0024] Figure 2 It is the structural diagram of the dual-channel experimental device;

[0025] Figure 3 It is the structural diagram of the bell mouth section;

[0026] Figure 4 It is the left view of the bell mouth section;

[0027] Figure 5 It is a top view of the bell mouth section;

[0028] Figure 6 It is a structural diagram of a circular sleeve pipe section;

[0029] Figure 7 Assembly diagram of circular sleeve pipe segment

[0030] Figure 8 It is a structural diagram of the airflow structure section;

[0031] Fig. 9 It is the assembly relationship diagram of the airflow structure section;

[0032] Fig.10 It is the structural relationship diagram of the experimental section;

[0033] Fig.11 It is the assembly relationship diagram of the experimental segments;

[0034] Fig.12 It is the structural relationship diagram of the transmission shaft fixing seat;

[0035] Fig.13 It is a side view of the transmission shaft fixing seat;

[0036] In the figure: 1- bell mouth section; 2- circular sleeve tube section; 3- airflow structure section; 4- experimental section; 5- bell mouth section casing; 6- inner and outer channel partitions; 7- inner channel straightening cone; 8- inner and outer channel guide plates; 9- circular sleeve tube section casing; 10- reserved holes; 11- inner channel flow passage; 12- inner hub fixing ring; 13- airflow structure section casing; 14- outer channel flow passage; 15- transmission shaft fixing seat; 16- experimental section blades; 17- experimental section straightening cone; 18- experimental section casing; 19- flange; 20- spindle; 21- transmission shaft; 22- front row threaded holes; 23- rear row threaded holes. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described below in conjunction with the accompanying drawings, but is not limited thereto. Any modification or equivalent replacement of the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention should be included in the protection scope of the present invention.

[0038] The present invention provides a dual-channel experimental device for constructing the inlet flow field of a small-diameter high-ratio compressor, which mainly includes the following innovative research:

[0039] (1) The wind tunnel outlet flow field is segmented to divide the wind tunnel flow into inner channel flow and outer channel flow.

[0040] (2) The inner and outer channels can be adjusted separately to achieve a large gradient distribution of the aerodynamic parameters of the inlet flow of the experimental section along the radial direction.

[0041] (3) The experimental equipment has a simple structure and is easy to process and disassemble.

[0042] (4) The flow field structure section is long enough to provide the possibility of installing multiple flow regulating devices.

[0043] (5) The transmission shaft fixing seat in front of the experimental section straightening cone can fix the transmission shaft. If the inner channel is equipped with adjustable guide vanes, the transmission shaft can be connected to the inner channel adjustable guide vanes to adjust the installation angle of the inner channel adjustable guide vanes.

[0044] Combine the following Figures 1 to 11 The present invention is described in further detail.

[0045] like Figure 1 and Figure 2As shown, the assembly sequence of the dual-channel experimental device for constructing the inlet flow field of a small-diameter-height ratio compressor is as follows: the bell-mouth section casing 5 of the bell-mouth section 1 at the inlet of the experimental device is connected to the circular sleeve section casing 9 of the circular sleeve section 2 by installing fixing bolts on the flange 19; the airflow construction section casing 13 of the airflow construction section 3 is respectively connected to the circular sleeve section casing 9 of the circular sleeve section 2 and the experimental section casing 18 of the experimental section 4 by the flange 19, and the inner channel straightening cone 7 is connected to the experimental section transmission shaft fixing seat 15 by the mandrel 20 to ensure the coaxial connection and stability of each component. The bell-mouth section 1 and the coaxially installed circular sleeve section 2, airflow construction section 3 and experimental section 4 casings are connected to the shaft by fixing bolts, which is convenient for the disassembly, assembly, maintenance and replacement of each device.

[0046] like Figure 3 to Figure 5 As shown, the bell-mouth section is located at the front end of the device and connected to the wind tunnel outlet to accelerate the wind tunnel flow. The bell-mouth section 1 is composed of a bell-mouth section casing 5. The contraction curve of the bell-mouth section casing 5 adopts the Vickers curve to achieve stable acceleration of the wind tunnel outlet airflow. The Vickers curve is the Vyshinsky curve. The use of the Vickers curve can alleviate the problem of too fast contraction at the inlet of the experimental device, ensure uniform and stable outlet velocity distribution, and obtain relatively good airflow quality. The Vickers curve formula is as follows:

[0047]

[0048] Where: H is the radius of the cross section at any axial position x; H0 is the inlet radius of the bell mouth section; H i is the exit radius of the bell mouth section; L is the axial length of the middle casing flow channel.

[0049] like Figure 6 As shown, the circular sleeve tube section 2 is composed of a circular sleeve tube section casing 9, inner and outer channel partitions 6, an inner channel rectifying cone 7 and four inner and outer channel guide plates 8 evenly distributed along the circumference. The inner and outer channel partitions 6 extend through the inner and outer channel guide plates 8 to the inlet of the experimental section 4, dividing the wind tunnel flow into an inner channel flow channel 11 and an outer channel flow channel 14; the circular sleeve tube section casing 9 is connected to the bell-mouth section casing 5 of the bell-mouth section 1 by 12 fixing bolts evenly arranged around the flange.

[0050] like Figure 7 As shown, the inner and outer channel partitions 6 and the inner channel rectifying cone 7 are evenly distributed with four guide plate grooves along the circumferential direction, and the inner and outer channel guide plates 8 pass through the inner channel rectifying cone 7 and the guide plate grooves on the inner and outer channel partitions 6 in sequence from the inside of the inner channel rectifying cone 7 and are welded together with the circular sleeve pipe section casing 9. The inner and outer channel guide plates 8 are connected to the circular sleeve pipe section casing 9 and the inner channel rectifying cone 7 to support the inner and outer channel partitions 6 and the inner channel rectifying cone 7. Since they are far away from the inlet of the experimental section, the influence of the inner and outer channel guide plates 8 on the inlet of the experimental section 4 is reduced.

[0051] like Figure 8 and Fig. 9 As shown, the airflow construction section 3 is located at the inlet of the experimental section 4, and is connected to the circular sleeve pipe section casing 9 by 18 fixing bolts uniformly arranged circumferentially on the flange 19. Different inner and outer channel flow fields can be constructed by adding a flow regulating device to the airflow construction section 3, so as to achieve a large gradient distribution of radial parameters at the compressor inlet. The airflow construction section 3 is composed of an airflow construction section casing 13 and a mandrel 20. The airflow construction section casing 13 has a row of reserved holes at a distance of 10 cm from the inlet and outlet. The reserved holes 10 closer to the inlet of the airflow construction section 3 can be installed with turbine blades, compressor blades and vortex screens for the total pressure and velocity of the flow field. The reserved holes closer to the outlet of the airflow construction section 3 can be installed with spoiler rods and adjustable guide vanes for the simulation of incoming flow wake and the adjustment of the inlet airflow angle. The specific installation components can further optimize the radial distribution of the incoming flow parameters according to the experimental requirements. An inner hub fixing ring 12 is arranged at the front and rear ends of the mandrel 20, and the inner channel straightening cone 7 and the transmission shaft fixing seat 15 are connected by an external connection method of bolts and nuts to ensure the coaxial installation of the experimental device and the stability of the experimental structure. The inner and outer channel partitions 6 in the circular sleeve pipe section 2 pass through the airflow structure section casing 13 and the mandrel 20, dividing the flow channel in the airflow structure section 3 into the inner channel flow channel 11 and the outer channel flow channel 14.

[0052] like Figure 10 to Figure 13 As shown, the test section 4 is composed of a test section casing 18, a test section blade 16 and a test section straightening cone 17, wherein: the outer wall of the test section straightening cone 17 is evenly distributed with a plurality of test section blades 16 along the circumferential direction, and the front end of the test section straightening cone 17 is provided with a transmission shaft fixing seat 15, the transmission shaft fixing seat 15 is connected to the test section straightening cone 17 through the rear row of circumferentially evenly distributed rear internal threads 23 arranged at its rear end and bolts, the transmission shaft fixing seat 15 is fastened to the inner hub fixing ring 12 through the front row of circumferentially evenly distributed front threaded holes 22 arranged at its front end and bolts, and the transmission shaft fixing seat 15 is installed on the transmission shaft 21 through interference fit. The transmission shaft 21 can be connected to a motor, and the motor drives the transmission shaft 21 to realize the rotation of the blades 16 of the test section.

[0053] The dual-channel experimental device of the present invention can realize the flow field construction that is difficult to complete with a single flow channel - the inner and outer channel partitions divide the flow from the experimental section into inner and outer channel fluids, ensuring that the inner channel and outer channel fluids are independent of each other; by adding a flow regulating device to the airflow construction section to construct different inner channel and outer channel flow fields, a large gradient distribution of radial parameters at the compressor inlet is achieved.

[0054] The dual-channel experimental device of the present invention can increase the flow field velocity by adding turbine guide vanes to the reserved holes at the inlet of the airflow structure section 10 cm away from the airflow structure section in the axial direction, reduce the flow field velocity by adding compressor blades, reduce the total flow field pressure by adding spoilers, simulate the incoming flow wake by adding spoiler rods to the reserved holes at the outlet of the airflow structure section 10 cm away from the airflow structure section in the axial direction, change the inlet angle of attack by adding adjustable guide vanes, and the corresponding flow regulating device can be selectively installed in the airflow structure section according to specific requirements.

Claims

1. A dual-channel experimental device for constructing the compressor inlet flow field, characterized in that The dual-channel experimental device comprises a bell mouth section, a circular sleeve pipe section, an airflow construction section and an experimental section which are connected in sequence, wherein: The bell mouth section includes a bell mouth section casing; The circular sleeve tube section comprises a circular sleeve tube section casing, and inner and outer channel partitions, an inner channel rectifying cone and inner and outer channel guide plates arranged inside the circular sleeve tube section casing; The airflow construction section comprises an airflow construction section casing and a mandrel arranged inside the airflow construction section casing; The experimental section includes an experimental section casing, and experimental section blades and an experimental section rectifying cone arranged inside the experimental section casing; The inner and outer channel partitions and the inner channel rectifying cone are evenly distributed with a plurality of guide plate grooves along the circumferential direction, and the inner and outer channel guide plates are connected to the circular sleeve pipe section casing by sequentially passing through the inner channel rectifying cone and the guide plate grooves on the inner and outer channel partitions from the inside of the inner channel rectifying cone; The inner and outer channel partitions extend from the inlet of the circular sleeve tube section to the outlet of the airflow construction section, dividing the flow channel of the airflow construction section into an inner channel flow channel and an outer channel flow channel; The outer wall of the experimental section straightening cone is provided with a plurality of experimental section blades evenly distributed along the circumferential direction, and a transmission shaft fixing seat is provided at the front end of the experimental section straightening cone; The two ends of the mandrel are respectively connected to the inner channel rectifying cone and the experimental section transmission shaft fixing seat.

2. The dual-channel experimental device for constructing the compressor inlet flow field according to claim 1 is characterized in that The lower end of the circular sleeve tube section casing is fastened together with the bell-mouth section casing by an external connection method using bolts and nuts evenly arranged circumferentially of the flange; the upper end of the circular sleeve tube section casing is fastened together with the lower end of the airflow structure section casing by an external connection method using bolts and nuts evenly arranged circumferentially of the flange; and the upper end of the airflow structure section casing is fastened together with the lower end of the test section casing by an external connection method using bolts and nuts evenly arranged circumferentially of the flange.

3. The dual-channel experimental device for constructing the compressor inlet flow field according to claim 1 is characterized in that The inlet and outlet of the airflow structure section casing are each provided with a row of reserved holes. The reserved holes at the inlet are used to install turbine blades, compressor blades or vortex screens for constructing the total pressure and velocity of the flow field, and the reserved holes at the outlet are used to install spoiler rods or adjustable guide vanes for simulating incoming flow wakes and adjusting the inlet airflow angle.

4. The dual-channel experimental device for constructing the compressor inlet flow field according to claim 1 is characterized in that The contraction curve of the bell-mouth section casing adopts the Vickers curve.

5. The dual-channel experimental device for constructing the compressor inlet flow field according to claim 4 is characterized in that The Vickers curve formula is as follows: Where: H is the radius of the cross section at any axial position x; H0 is the inlet radius of the bell mouth section; H i is the exit radius of the bell mouth section; L is the axial length of the middle casing flow channel.

6. The dual-channel experimental device for constructing the compressor inlet flow field according to claim 1 is characterized in that An inner hub fixing ring is arranged at the front end and the rear end of the spindle respectively, and the inner channel fairing cone and the transmission shaft fixing seat are connected by an external connection method of bolts and nuts.

7. The dual-channel experimental device for constructing the compressor inlet flow field according to claim 1 is characterized in that The transmission shaft fixing seat is connected to the test section straightening cone through the rear row of circumferentially evenly distributed internal threads and bolts arranged at its rear end, and the transmission shaft fixing seat is fastened to the inner hub fixing ring of the spindle through the front row of circumferentially evenly distributed front threaded holes arranged at its front end and bolts.

8. The dual-channel experimental device for constructing the compressor inlet flow field according to claim 1 is characterized in that The transmission shaft fixing seat is installed on the transmission shaft through interference fit, the transmission shaft is connected to the motor, and the motor drives the transmission shaft to realize the rotation of the blades of the experimental section.

Images