JPH06273263A - Wind tunnel - Google Patents

Abstract

PURPOSE:To reduce the dimension of a supporting device for a model suppress the disturbance of the airstream in a wind channel, and prevent the unnecessary inertial force from being measured in the dynamic aerodynamic test. CONSTITUTION:The dimension of a supporting device for a model is reduced by installing a model 4 arranged and fixed in an air stream 7 in a wind channel 1, and the air stream changing walls 13a and 13b which change the attitude angle for the air stream 7 in the wind tunnel are installed in the peripheral part of the model 4, and the direction of the air stream in the wind channel 1 is changed by moving the air stream changing walls 13a and 13b, and the angle of attack of the model 4 is changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wind tunnel used for measuring static aerodynamic force and dynamic aerodynamic force acting on a model of an aircraft or the like.

[0002]

2. Description of the Related Art In a conventional wind tunnel, as shown in FIG. 3, an arcuate strut-shaped model support device 2 is set in the wind tunnel 1, a sting 3 is attached to the model support device 2, and a test model is attached to the tip thereof. 4 was attached via a balance 5. In order to change the posture angle 6 of the test model 4, in other words, the angle of attack with respect to the air flow 7, the model support device 2 was driven by the driving roller 11.

Further, in order to measure the dynamic aerodynamic force, the drive unit 8 set in the model supporting device 2 applies a forced pitching vibration of an angle of 10 to the sample model 4 around the center of rotation. ing.

[0004]

In the above-mentioned conventional wind tunnel, the model support device needs to be strong from the viewpoint of strength and vibration, which has been a cause of disturbing the air flow in the wind tunnel.
Further, in dynamic aerodynamic force measurement, unnecessary inertial force has to be measured, which is disadvantageous in that it takes time to analyze.

The present invention is intended to provide a wind tunnel capable of solving the above problems.

[0006]

A wind tunnel according to the present invention comprises a model which is arranged and fixed in an air flow in the wind tunnel, and an air flow deflection which is arranged in a peripheral portion of the model and has a variable attitude angle with respect to the air flow in the wind tunnel. It is characterized by having a wall.

[0007]

The wind tunnel of the present invention is constructed as described above, and when it is desired to change the angle of attack of the fixed model to the air flow, the air flow of the air flow diverting wall arranged in the peripheral portion of the model The posture angle is changed to change the direction of the air flow in the wind tunnel. This changes the direction of the air flow with respect to the fixed model and changes the angle of attack of the model.

Further, in dynamic aerodynamic force measurement, the angle of attack of a fixed model is periodically changed by periodically changing the posture angle of the airflow diverting wall to periodically change the direction of the airflow. Change.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIG. In this embodiment, as shown in FIG.
Is fixed to a vertical strut 12 supported from the outside of the wind tunnel 1 via a balance 5 and a sting 3.
The measurement unit 13 of the wind tunnel 1 in which the test model 4 is housed includes upper and lower walls 13a and 13b that form the walls of the wind tunnel. These walls 13a and 13b are driven by a drive device (not shown). The posture angle with respect to the airflow can be changed by performing a pitching motion in the direction of arrow 15 around the center of gravity 14 of No. 4. During the pitching movement of the walls 13a and 13b, the front edge 16 and the rear edge 17 of the walls 13a and 13b move up and down as shown in FIG.
6. The trailing edge 17 is connected to the flexible walls 18 and 19, respectively, and the other ends of the flexible walls 18 and 19 are connected to the wall surface 20 of the wind tunnel 1. The upper and lower walls 13a,
The pitching movement of 13b is performed in synchronization with both walls 13a and 13b being kept substantially parallel to each other. Further, when the upper and lower walls 13a and 13b perform a pitching motion, the upper and lower walls 13a and 13b slide with airtightness against the side walls of the wind tunnel by a sealing device (not shown) so that the air flow in the wind tunnel does not leak. You can do it.

In this embodiment, the upper and lower wall surfaces 1 of the measuring unit 13
When 3a and 13b are rotated by θ around the center of gravity 14 of the test model 4 by a driving device (not shown) and the front edge 16 is directed downward, the airflow flowing in the direction of arrow 7 is indicated by the arrow in the measuring unit 13. 7a, and the angle of attack of the test model 4 is finally set to θ.

When the rotation angles of the upper and lower wall surfaces 13a and 13b are changed periodically with respect to time, the angle of attack of the test model 4 also changes periodically.

As described above, in this embodiment, by rotating the upper and lower wall surfaces 13a and 13b of the measuring section, the angle of attack of the fixed test model 4 is set to a remaining value or periodically changed. Can be made. Also, the test model 4 is
It is fixed to the strut 12 supported from the outside of the wind tunnel 1 via the balance 5 and the sting 3 and does not drive the test model 4, so the supporting device for the test model 4 is downsized, and the airflow is reduced. Will not be disturbed. Also, in the dynamic wind tunnel test, unnecessary inertial force of the test model 4 and its supporting device is not required to be measured in the part where the angle of attack of the test model 4 is changed periodically, which facilitates the analysis. .

A second embodiment of the present invention will be described with reference to FIG. In this embodiment, as in the first embodiment, the test model 4 fixed in the vertical strut 12 supported from the outside of the wind tunnel 1 via the balance 5 and the sting 3 is provided in the wind tunnel 1. Rotation around the center of gravity 14, that is, arrow 15 in the figure
A cylinder 21 having a rectangular cross section that makes a pitching motion in the direction of is provided. In addition, 20 is a wall surface which forms the flow path of the wind tunnel 1.

Also in this embodiment, the direction of the air flow flowing around the sample model 4 is changed by the pitching movement of the cylinder 21, and the same action and effect as those of the first embodiment can be obtained.

[0015]

As described above, in the wind tunnel according to the present invention, the model itself is fixed, and the posture of the airflow deflecting wall around the model is variable with respect to the airflow. This makes it possible to reduce the turbulence of the air flow. Further, in the dynamic wind tunnel test, since the model is fixed, it is not necessary to measure an unnecessary inertial force, which facilitates the analysis.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a first embodiment of the present invention.

FIG. 2 is a schematic diagram of a second embodiment of the present invention.

FIG. 3 is a schematic view of a conventional wind tunnel.

[Explanation of symbols]

 1 Wind tunnel 3 Sting 4 Test model 5 Balance 7, 7a Airflow 12 Strut 13 Measuring part 13a, 13b Measuring part wall 15 Pitching direction 18, 19 Flexible wall 20 Wind tunnel wall 21 Cylinder

Claims (1)

[Claims] 1. A wind tunnel, comprising: a model arranged and fixed in an air flow in the wind tunnel, and an air flow deflecting wall arranged in a peripheral portion of the model and having a variable attitude angle with respect to the air flow in the wind tunnel. .