JPH01132923A - Truncated cone-shaped model wind tunnel testing apparatus equipped with power - Google Patents

Abstract

PURPOSE:To reduce the interference exerted on a balance apparatus by high pressure air supply piping at the measuring time of air force in a wind tunnel test, by providing a balance driving apparatus, the balance apparatus, a truncated cone-shaped model and a shaft coupling. CONSTITUTION:When high pressure air is sent in a shaft coupling 34 from the take-in port thereof, said air passes through a high pressure rubber hose 35 from the passing hole of a revolving cylinder through the interior of the revolving cylinder to be supplied to an engine 44 as a power source from the valve chamber 45 of a truncated cone- shaped model. A cylinder 15 is revolved by operating a balance driving apparatus 10 and the revolution, that is, elevation of the truncated cone-shaped model is changed to measure the component force at that time by a balance apparatus 20. In this case, the hose 35 imparts the degree of freedom of the movement in a horizontal plane and that of the rotation around the shaft present in the horizontal plane at the upper end thereof and the shaft coupling 34 imparts the degree of freedom of the movement in a vertical direction and that of the rotation around a vertical shaft. By this method, the interference exerted on the apparatus 20 by a high pressure gas supply apparatus 30 at the measuring time of air force in a wind tunnel test is reduced.

Description

[Detailed Description of the Invention] [Industrial Application] This invention provides a powered half-cut model wind area that can supply high-pressure air for driving a model engine with almost no interference to the model's aerodynamic measurement. It is related to the device.

[Conventional technology]

Conventionally, this type of model wind field device has used a full model rather than a half-cut model, and has been equipped with piping to provide power for measurements.

In this case, as a method to remove interference caused by piping, 1)
Various methods have been tried, including a method of combining two gimbal-type bellows, 2) a method of combining high-pressure rubber hoses in a crank shape, and 3) a method of combining an air joint and a bellows.

[Problem that the invention seeks to solve]

By the way, the method 1) above maintains linearity with respect to balance interference, but has drawbacks such as hysteresis peculiar to bellows and a large amount of interference. Although the method 2) reduces the amount of interference, it is difficult to ensure reproducibility of the amount of interference during installation and removal. In addition, in method 3), the amount of interference is extremely small, but since the shaft in the air joint is suspended by the balance of aerodynamic forces, the height of the shaft changes due to changes in air pressure, and the height of the shaft inside the joint changes. There is a drawback that actual handling such as adjusting the spacing between the shafts is not easy. .

This invention was made in order to improve the shortcomings of these conventional methods, and is a powered half-cut model that minimizes the interference of the model engine WJA dynamic high-pressure air supply piping with the balance device when measuring aerodynamic force in a wind region. The purpose is to provide wind field equipment to Party B.

[Means for solving problems]

The powered half-cut model wind field device according to the present invention includes a balance wA! attached to a fixed member. gIl device; a balance device that is rotated by this balance drive device; a half-cut model that is mounted on this personnel device and positioned in the wind tunnel measurement section; and a half-cut model that is attached to a fixed member and can be rotated and moved in the axial direction. and a high-pressure gas supply device comprising a high-pressure rubber hose that communicates the shaft joint with the half-cut model and supplies the high-pressure gas from the intake port to the half-cut model as a power source. ;

[Operation] In the present invention, high-pressure gas supplied from the intake port of the shaft joint is applied as power to the half-cut model through a high-pressure rubber hose, and required measurements are performed using a balance device.

〔Example〕

FIG. 1 is a partially broken sectional view showing an embodiment of the present invention.

In this figure, ■ is the equipment part, ■ is the wind tunnel measurement part, and ■ is the floor surface. Device section ■ Balance drive value 'IN, 10. Balance device 20
．． The wind tunnel measuring section (2) is a conventionally known one, and is designed to generate an air flow at a required wind speed. It is attached.

Next, details of each part will be explained.

The balance driving device 1o is configured as follows.

A fixing member 11 is fixed to the floor surface ■, and the housing 1 is fixed to this.
2 is attached. Further, an inner cylinder 15 is rotatably supported by bearings 13 and 14, and a worm wheel 17 is supported by a support member 16 attached to this inner cylinder 15. In FIG. 1, since it is not necessary for the inner cylinder 15 to rotate by 3.60', a portion of the worm wheel 17 is shown. A worm 18 meshes with the worm wheel 17, and by rotating the worm 18, the inner cylinder 15 rotates.

The large scale W21 is mounted on the inner cylinder 15, and a swing frame 23 is attached to the outer casing 21 via a balance support mechanism 22, and a through hole 24 is provided in the center of the swing frame 23. The structure is as follows.

Note that a detector for detecting each component force is attached to the balance support mechanism 22, but since the balance device 20 itself is well known, the details thereof will be omitted.

The high pressure gas supply device 30 is configured as follows. A fixing ring 31 is attached to the lower surface of the housing 12 of the balance drive device 10.
, and a shaft joint 34 is fixed on a mounting plate 33 to which four pillars 32 are attached. And the shaft joint 3 with
4, one end of a high-pressure rubber hose 35 is connected to the connector 36, and the other end is connected to the half-cut model 40 by a connector 37.3. The high pressure rubber hose 35 is, for example, 3
It has multiple rubber layers with a reinforcing steel mesh interposed between each rubber layer.

As shown in detail in FIG. 2, the shaft joint 34 includes an f-side base 34a having a through hole 24 in the center, an upper base 9634b fixed to this and also having a through hole 24 in the center;
The rotating tube 34c is basically composed of a rotating tube 34c, and a high-pressure gas intake port 34d is formed on the side surface of the ascending base 34b, and the rotating tube 34c has a fluororesin etc. attached to the lower base 34m and the upper base 34b. Slide bearing 3 made of a material with good sliding properties
4a so as to be rotatable and movable in the axial direction, and furthermore, a high-pressure gas passage hole 34f and a flange 34g are formed in the rotation n34c, and as shown in FIG. Then, this flange 34g and the flange 36a of the connector 36 are connected.

The half-cut model 4o has a fuselage 41, a main N422 tail and tail 432 engine 44, a valve chamber 45 is provided in the fuselage 41, and a connector 37 is attached to the lower part of the valve chamber 45.

Although not shown in the figure, the pressure of the high pressure gas supplied from the valve chamber 45 is adjusted individually to the engine 44.
It is now possible to supply Note that 46 indicates a mounting plate.

FIG. 3 shows an exploded perspective view of the embodiment of FIG. 1.

However, the balance driving device 10 is omitted. Also, the third
The figure shows the relationship between the half-cut model 4o and each component force, direction of wind speed, etc. Table 1 also shows the balance capacity for each component of force.

Indicates balance accuracy.

Table 1 Next, the operation will be explained.

When high pressure gas is sent from the intake port 34d of the shaft joint 34,
This is the rotation I from the passage hole 34f of rotation 1ff134c!
It is supplied to the engine 44 as a power source from the valve chamber 45 of the half-cut model 40 through the high-pressure rubber hose 35 through the L cylinder 34c. Then, by operating the balance WE moving device 10, the inner cylinder 15 is rotated, the rotation of the half-cut model 4o, that is, the angle of attack is changed, and the component force at that time is measured by the balance device 20.

In this case, the ^IO rubber hose 35 provides freedom of movement in the horizontal plane and rotation around the shaft in the horizontal direction at its -F end, and the external force shaft joint 34 allows freedom of movement in the horizontal plane. Provides freedom of movement and rotation around the vertical axis. Hence, the normal force (FM).

Interference with the 4 component forces of axial force (1"A), rolling moment 1. (M, ) and yawing moment (MZ) is absorbed by the degree of freedom of the high pressure rubber hose 35, and m force (FY)
Interference with pitching moment +-(Mv) is absorbed by the shaft joint 34. The positive direction of the six-component force acting on the half-cut model 40 is as shown in FIG.

However, in practice, piping interference cannot be completely eliminated for the following reasons.

1) Since the high-pressure rubber hose 35 has rigidity, the above-mentioned movement and rotation are not completely free.

2) When high pressure air is supplied into the high pressure rubber hose 35,
The high-pressure rubber hose 35 is expanded, thereby increasing the rigidity of the piping. 3) The rotating tube 340 of the shaft joint 34 and both base portions 34a.

34b and the high pressure rubber hose 35.
Because of torsional rigidity, movement along a vertical axis and rotation around that axis are not completely free.

However, if the amount of interference that actually appears is sufficiently small and stays within a range smaller than the accuracy of the aerodynamic force measured by the balance device 2o, the piping interference will be negligible.

In order to confirm that the device of the present invention satisfies such conditions W4, three types of interference amounts were measured corresponding to the above 1) to 3).

1) In the powered half-cut model wind field device of the present invention, the load is taken into account on the model, and the balance output at that time is calculated by the high-pressure gas supply device 30.
Compare with that without installing. The difference between the two is the amount of piping interference.

2) Supply high-pressure air into the high-pressure gas supply device 30, and examine changes in the amount of pipe interference due to the supplied air.

3) Give rotation of the vertical axis to the half-cut model 40 and examine the amount of piping interference. This test result will be explained with reference to Fig. 4. Fig. 4(a) shows the change in the axial force F^, which is most sensitive to piping interference, with respect to the large scale weight W^. According to this, 19sΔF
' Indicates A. In this case as well, ΔF is well within the range of balance accuracy.

FIG. 4(C) shows no interference of the pitching moment (MY), which is closely related to rotation around the vertical axis.

Rotation of shaft joint 34 rWJ34c and both bases 34a, 34b
There is hysteresis due to [1 between .

Figures m5 (a) and (bl) show the amount of interference of the high pressure gas pressure with the axial force and the rotation rI of the shaft joint 34 when using the high pressure gas supply device 3o configured by combining two conventional gimbal bellows. !J cylinder 34c and both bases 34a, 3
Figures 6(a) and 6(b) are a diagram showing the amount of interference to pitching moment +- (Mv) caused by eta between 4b and torsional rigidity of the high-pressure rubber hose 35. FIG. 5(a) shows a case where the method of combining the shapes in the form of (o) is used.

It is a figure showing the amount of interference similar to (b).

Comparing FIGS. 5(a), (b), FIGS. 6(a), (b), and FIGS. 4(b), (c), it can be seen that the amount of interference according to this invention is extremely small. It's obvious.

As described above, by using the device of the present invention, the interference of the high-pressure gas supply device 30 with the model aerodynamic force measuring balance can be reduced to a virtually negligible level.

〔Effect of the invention〕

As explained above, the present invention includes a balance drive device attached to a fixed member; a balance device rotated by this balance drive device; and a half-cut model housed on this balance device and positioned in a wind tunnel measurement section. and; a shaft joint that is attached to a fixed member and is rotatable and movable in the axial direction and is equipped with an intake port for high-pressure gas; A high-pressure gas supply device consisting of a high-pressure rubber hose to be used as a power source;
Since it is equipped with vertical force (F~) and axial force (FA).

Interference with the 4-component forces of rolling moment l-(MX) and yawing moment (Mχ) is absorbed by the degrees of freedom of the high-pressure rubber hose (7), and interference with lateral force (11°Y) and pitching moment (MY) (when the hexagonal joint Compared to the conventional method (7), it has fewer components and is less expensive, and not only can the amount of interference with the balance device be reduced, but it is also easy to handle, and it is easy to install on the balance device. It has many benefits such as high dimensional reproducibility.

[Brief explanation of the drawing]

[Figure] is a side view showing an embodiment of the present invention with main parts cut away, Figure 2 is a partially cutaway front view showing details of the shaft joint in Figure 1, and Figure 3 is a partially cutaway side view showing an embodiment of the present invention. , an exploded perspective view of FIG. 1, FIGS. 4(a) to 4(e) are diagrams showing various amounts of interference according to the present invention, and FIG. 5(a). (b) and FIGS. 6(a) and 6(b) are diagrams showing various amounts of interference when the conventional high-pressure gas supply device lf is used. . In the figure, 10 is a balance drive device, 11 is a fixed member, 15ζ is an inner cylinder, 16 is a support member, 17 is a wormhole base, 34
c is the rotation rJIJJ cylinder, 34d is the intake port, 34e is the sliding bearing, 35 is the high pressure rubber hose, 36 and 37 are the connectors, 40
41 is the fuselage, 42 is the main wing, 43 is the tail, 4 is the semi-contact model.
4t is the engine, 45 is the valve chamber. Patent Applicant Aerospace Technology 1-[Research Director Hideo Nagasu 1st
Figure 2 Figure 3 Figure 4 Soil i! LMtQTpfref'l - Fig.5 rl-1

Claims (1)

[Claims] a balance drive device attached to a fixed member; a balance device rotated by the balance drive device; a half-cut model attached to the balance device and positioned in the wind tunnel measurement section; a half-cut model attached to the fixed member and rotated. and a shaft joint movable in the axial direction and equipped with a high-pressure gas intake;
a high-pressure gas supply device comprising a high-pressure rubber hose that communicates the shaft joint with the half-cut model and supplies high-pressure gas from the intake port to the half-cut model as a power source; Trial device.