JPH0489543A - Wind tunnel tester - Google Patents

Abstract

PURPOSE:To enable measurement of an aerodynamic dynamic differential coefficient about a roll shaft without requiring a large driver by mounting a blade at a rear end of a sting supporting a model and rotating the sting utilizing an pneumatic force working on the blade. CONSTITUTION:When a rotating shaft 14 is rotated with a driver 15 according to a command of a controller 12 to change an angle alpha of twisting of a blade 13, a pneumatic force works on the blade 13 and a moment l is generated so as to rotate a sting 3 about a longitudinal shaft. The sting 3 can be rotated utilizing the moment l and moreover, a desired angular velocity of rotation can be obtained by controlling the angle alpha of twisting of the blade 13. A driving force necessary for the driving of the blade 13 can be very small if the center of rotation of the blade 13 is selected properly. This enables the measurement of an aerodynamic dynamic differential coefficient about a roll shaft by a small driving force with a simple device.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to improving the performance of a wind tunnel testing device for measuring the aerodynamic motivation coefficient around the roll axis of an aircraft, flying object, etc. through wind tunnel testing. .

[Conventional technology]

FIG. 2 is an explanatory diagram of a conventional wind tunnel test device, in which (1) is the measurement section, (2) is the model, and (3) is the sting.

(4 are struts, (5) is a balance device, (6) is a drive device, (7) is a heald (8) that transmits the driving force of the drive device to the sting (3) is a measuring device, (9) is a sting The angular velocity sensor (10) that detects the rotational angular velocity of (3) is a sling ring that transmits the output of the balance device (5), (
11) is a signal cable, and (12) is a control device for the drive device (6). When designing an aircraft or flying vehicle, there is a need to predict its aerodynamic performance, and for this purpose the wind tunnel test equipment shown in Figure 2 is used. Using compressed air, a blower, etc., a constant speed airflow is generated in the measurement unit (1), and a scale model (2) of an aircraft or flying object is placed in it. It is installed via a strand (5), and the aerodynamic force applied to the model (2) is measured by a balance device (5).

[Problem to be solved by the invention]

Model (2)
is forcibly rotated around the machine axis in the measuring part (1),
It is necessary to measure the moment around the machine axis acting on the model (2) and the rotational angular velocity at that time. That is, the aerodynamic motivation coefficient C1p around the roll axis is given by the following equation.

Cl p=Cl * (2V) /P Here, CI is a coefficient obtained by making the moment around the machine axis acting on the model (2) during rotation dimensionless using the dynamic pressure of the wind tunnel airflow and the reference area, and ■ is the coefficient of the wind tunnel airflow. The velocity, P, is the rotational angular velocity of the model (2). In conventional wind tunnel test equipment, the sting (3) is driven using a drive device (6) and a belt (7),
Model (2) was being forced to rotate. Model while rotating (2)
The moment acting around the machine axis is measured by a balance (5) and transmitted to a measuring device (8) via a slip ring (10) and a signal cable (11). Also, the model (2
) is the rotational angular velocity.

Detected by the angular velocity sensor (9) and connected to the signal cable (
11) to the measuring device (8) and the control device (12). The control device (12) transmits a control command to the drive device (6) via the signal cable (11) so as to maintain the rotational angular velocity at a predetermined value. From the data obtained as described above, the aerodynamic motivation coefficient ctp around the roll axis
can be calculated.

However, with this method, Sting (3) and Model (2)
The entire body must be rotated by overcoming the large aerodynamic force acting on the entire sting (3) and model (2), so a large driving force is required to obtain a sufficient number of revolutions for measurement, and the drive device ( 6) The problem was that it was large and consumed a lot of energy.

This invention was made to solve this problem, and by attaching a wing to the rear end of the sting that supports the model and rotating the sting using the aerodynamic force acting on the wing, a large drive device can be created. The purpose of this invention is to obtain a wind tunnel test device capable of measuring the aerodynamic motive coefficient around the roll axis.

[Means to solve the problem]

The wind tunnel test device according to the present invention has a wing attached to the rear end of a sting that supports a model, so that the sting can be rotated by utilizing the aerodynamic force acting on the wing.

[Effect]

In this invention, the sting was attached to the rear end in the air stream. When you twist the wing, aerodynamic force acts on the wing.

A moment is generated that tries to rotate the sting around its longitudinal axis. This moment can be used to rotate the sting. Furthermore, by controlling the twist angle of the blade, a desired rotational angular velocity can be obtained. At this time, the driving force required to move the blade can be extremely small if the center of rotation of the blade is selected appropriately.

〔Example〕

FIG. 1 is an explanatory diagram showing one embodiment of the present invention. In FIG. 9, (13) is a blade, and (14) is a rotation axis of the blade (13).

(15) is a drive device. The wind tunnel test equipment starts up.

When the measurement is possible, the control device (12) installs the slip ring (1) on the drive device (15) under preset conditions.
0) and a signal cable (11).

The drive device (15) drives the blade (13) around the rotation axis (14) according to the command, thereby giving the blade (13) a twisting angle α.

When the wing (13) has a twist angle α with respect to the airflow, the wing (13)
) is affected by an air force proportional to α. If the twist angle α of the blade (13) is set in opposite left and right directions, a moment 1 will be generated around the longitudinal axis of the sting (3) due to the aerodynamic force. This moment l causes the sting (3) to rotate around its longitudinal axis. At this time, the moment acting on the model (2) around the machine axis is measured by the balance device (5) and transmitted to the measuring device (8) via the slip ring (]0) and the signal cable (11).

Further, the rotational angular velocity of the model (2) is detected by the angular velocity sensor (9) and transmitted to the measuring device (8) and the control device (12) via the signal cable (11). The control device (12) transmits a control command to the drive device (15) via the slip ring (10) and the signal cable (11) so as to maintain the rotational angular velocity at a predetermined value. Drive device (15)
rotates the single rotation shaft (14) according to commands from the control device (12), changes the twist angle α of the blade (13), and controls the magnitude of the moment p.

〔Effect of the invention〕

As explained above, the wind tunnel test device according to the present invention has the following features:
A wing is installed behind the Sting that is driven by a drive device, and the twist angle of this wing is controlled, and the aerodynamic force acting on the wing is used to rotate the Sting, which previously required a large-scale drive device. This method has the advantage that the aerodynamic motivation coefficient around the roll axis can be measured using a simple device and a small driving force.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram of a conventional wind tunnel test apparatus. In the figure, (1) is the measuring section, (2) is the model, (3) is the sting, (4) is the strut, (5) is the balance device, (
6) is a driving device, (7) is a helmet), (8) is a measuring device,
(9) is an angular velocity sensor, (10) is a slip ring,
(11) is a signal cable, (12) is a control device,
(13) is a blade, (14) is a rotating shaft, and (15) is a drive device. Note that the same symbols in Figure 9 indicate the same or equivalent parts.

Claims (1)

[Claims] Generate an airflow at a constant speed, place a model in the airflow,
In the wind tunnel test equipment that measures the aerodynamic force applied to the model,
A stay that is capable of rotating around a longitudinal axis while installing a model in an air stream, a balance device that measures aerodynamic force, a measuring device, an angular velocity sensor that detects the rotational angular velocity of the stay, and a stay attached to the rear of the stay. wings and
A rotating shaft attached to the blade, a drive device coupled to the rotating shaft, a control device, the output of the balance device to the measuring device, the signal from the angular velocity sensor to the control device, and the control device. A wind tunnel test device comprising a signal cable for transmitting commands from a control device to the drive device, and a slip ring.