Search

CN-119413389-B - Test fixture for engine pneumatic probe closed wind tunnel rotating window

CN119413389BCN 119413389 BCN119413389 BCN 119413389BCN-119413389-B

Abstract

The invention discloses an engine pneumatic probe closed wind tunnel rotating window test fixture which comprises a disc base, wherein the disc surface of the disc base is fixedly connected with one end of a symmetrical wing-shaped support arm, the other end of the symmetrical wing-shaped support arm is fixedly connected with the outer side wall of a cylindrical fairing, a pore canal which is mutually communicated and used for installing a pneumatic probe is arranged on the disc base, the symmetrical wing-shaped support arm and the cylindrical fairing, the pore canal in the symmetrical wing-shaped support arm is a cavity hole matched with the installation part of the pneumatic probe, and the detection part of the pneumatic probe penetrates through the pore canal in the cylindrical fairing and extends into the cylindrical fairing.

Inventors

  • ZHANG QIAN
  • LIU PINGLIN
  • SONG SHIFENG
  • ZHAO XIAOYANG
  • YANG XIANWEN
  • DU ZHENZHI
  • LI ZENGGANG

Assignees

  • 成都凯天电子股份有限公司

Dates

Publication Date
20260512
Application Date
20241031

Claims (7)

  1. 1. The utility model provides a wind tunnel window test fixture is closed to engine pneumatic probe, its characterized in that includes disc base (1), the quotation of disc base (1) is fixed connection with the one end of symmetry wing support arm (2), the other end of symmetry wing support arm (2) is fixed connection with the lateral wall of cylindrical radome fairing (3), be provided with a pore canal that communicates each other and be used for installing pneumatic probe (4) on disc base (1), symmetry wing support arm (2) and cylindrical radome fairing (3), and the pore canal that is located in symmetry wing support arm (2) is the die cavity hole that matches with the installation department of pneumatic probe (4), the detection part of pneumatic probe (4) runs through the pore canal that is located on cylindrical radome fairing (3) and stretches into in cylindrical radome fairing (3); The axis of the cylindrical fairing (3) is parallel to the disk surface of the disk base (1), a scribing line (5) is arranged on the disk surface of the disk base (1), and the scribing line (5) is perpendicular to the axis of the cylindrical fairing (3); The length of the symmetrical wing-shaped support arm (2) is determined according to the thickness of the boundary layer of the closed test section, and the difference between the length of the symmetrical wing-shaped support arm (2) and the thickness of the boundary layer of the closed test section is not less than 5cm.
  2. 2. The engine pneumatic probe closed wind tunnel rotating window test fixture according to claim 1 is characterized in that a circular truncated cone-shaped drainage hole (302) is formed in the front port of the cylindrical fairing (3), the large diameter end of the drainage hole (302) is connected with the outer edge of the front end of the cylindrical fairing (3) and forms an annular thin edge tip (301), and the small diameter end of the drainage hole (302) is smoothly connected with the inner circular surface of the cylindrical fairing (3).
  3. 3. The engine pneumatic probe closed wind tunnel rotating window test fixture according to claim 2, wherein the inclined angle of the conical surface of the drainage hole (302) is 20 degrees.
  4. 4. The engine pneumatic probe closed wind tunnel window test fixture according to claim 2, characterized in that the axial distance between the duct on the cylindrical fairing (3) and the annular feathered edge tip (301) is not less than 2 times the length of the detection part of the pneumatic probe (4).
  5. 5. The engine pneumatic probe closed wind tunnel rotating window test fixture according to claim 1, wherein the shape of the inner wall of the cylindrical fairing (3) is the same as the shape of the inner runner wall of the engine where the pneumatic probe (4) is installed.
  6. 6. The engine pneumatic probe closed wind tunnel rotating window test fixture according to claim 1, wherein the diameter of the cylindrical fairing (3) is 3-4 times the length of the detection part of the pneumatic probe (4).
  7. 7. The engine pneumatic probe closed wind tunnel rotating window test fixture according to claim 1, wherein the disc base (1) is fixed at a test section rotating window interface through a screw (6).

Description

Test fixture for engine pneumatic probe closed wind tunnel rotating window Technical Field The invention relates to the technical field of wind tunnel tests, in particular to a test fixture for a closed wind tunnel rotating window of an engine pneumatic probe. Background 1. Wind tunnel test The wind tunnel is a ground test equipment facility very important in the aviation industry, wind tunnel tests, numerical simulation and flight tests are three means of aerodynamic research, the theoretical basis of the wind tunnel tests is a motion relativity principle, when in actual flight, the air flow is static, the aircraft moves in the air flow, in the wind tunnel, the aircraft or the aircraft parts, the models and the like are fixed in a wind tunnel test area, and the air flow flows, so that the relative motion between the aircraft and the air flow is simulated when the aircraft flies. A product or model needs to be tested according to test conditions, the following points are mainly considered in the selection of the wind tunnel, namely the size of a test sample, the size of the wind tunnel, the highest test Mach number of the wind tunnel, the quality of a wind tunnel flow field, a wind tunnel test sample mounting interface, special test requirements and the like, an effective test area meeting the flow field quality requirements is arranged in the open wind tunnel or the closed wind tunnel, the effective test area of the closed wind tunnel is generally in the center area of the cross section of a test section, the specific range is determined according to flow field calibration results, the effective test area is approximately in the range of 60% -70% of the cross section, the effective test area of the open wind tunnel is also determined according to flow field calibration, and the effective test area of the open wind tunnel is generally not more than 60% of the size of the outlet cross section of a contraction section. The tested part of the test sample is positioned in the effective test area of the wind tunnel for testing. 2. Turbulent flow Laminar flow is a stable airflow movement mode, wherein airflow moves along a fixed and predictable streamline, turbulent flow is an unstable airflow movement mode, obvious transverse movement and vortex flow exist in turbulent airflow, laminar airflow can always keep a laminar movement state when flowing on the surface of an object with a limited-length continuous (streamline) shape, but when the continuous change direction of the surface of the object and the movement direction of the airflow exist a large angle, the pressure gradient in the forward direction is overlarge, and the turbulent flow or vortex flow can be changed. When the external surface of an object has discontinuous step change, airflow is disturbed by the step point and is subjected to rapid change, turbulent flow mixed with turbulent flow and vortex flow is formed near and downstream of the step point, turbulent flow time is changed, continuous unstable disturbance is caused to surrounding flow fields, and the disturbance form is influenced by various factors such as the external dimension of the disturbance point, the flow velocity and whether a constraint wall surface exists or not. 3. Pneumatic probe in engine A certain number of pneumatic probes are required to be installed in the aero-engine to measure the total pressure, static pressure and other internal pressures in different areas in the aero-engine, each pneumatic probe is required to be subjected to a pneumatic consistency test before being installed on the aero-engine so as to ensure that the pneumatic consistency test meets design and manufacturing indexes, and test equipment for carrying out the pneumatic consistency test on the pneumatic probes in the aero-engine is a wind tunnel. The pneumatic probe in the engine can be divided into a mounting part and a detecting part in the external structure, the mounting part is generally completely attached to a cavity surface reserved in the engine and positioned by a positioning pin, a pin groove and the like, and the mounting part is not exposed to air flow. And the probe of the detecting part extends into the internal flow passage of the engine to measure the air flow pressure. In general, for installation and positioning and fitting with the internal reserved profile of the engine, the installation part and the detection part of the pneumatic probe cannot be continuously changed in appearance, but edges and sharp angles with step changes exist, so that the following defects are generated: 1. Because the pneumatic probe mounting part and the probe part are not in smooth transition, step points (shown in figure 5) on the shapes of edges or sharp angles and the like exist, the step points are very close to the pressure measuring holes of the probe part, and in the wind tunnel test process, if the step points are directly exposed to air flow, turbulent flow areas (shown in figure 6) can be genera