JPH1114497A - Method and device for equalizing temperature distribution of stratified stream in width direction in temperature stratification wind tunnel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate a stratified stream wherein temperature distribution is even in width direction. SOLUTION: Relating to a temperature stratification wind tunnel wherein a wind entering a contraction barrel 7 is made into a stratified stream with a stratification cart 5 and sent to a measurement barrel 3, at both side positions of an inlet part of the stratification cart 5 of the contraction barrel 7, a border layer streaming device 29 comprising a border layer streaming plate 32 where an upper stream side end side is hinged to the contraction barrel 7 while angle can be adjusted in horizontal direction with a hinge part 31 and an angle adjusting mechanism part 33 for adjusting an angle of the border layer stream plate 32 against the contraction barrel 7 is attached.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for equalizing a temperature distribution in a stratified flow width direction in a temperature stratified wind tunnel, and more particularly, to a method for generating a stratified flow having a uniform temperature distribution in a width direction. The present invention relates to a method and an apparatus for uniformizing a temperature distribution in a stratified flow width direction of a temperature stratified wind tunnel to be obtained.

[0002]

2. Description of the Related Art FIGS. 3 to 5 schematically show an example of a conventional thermal stratified wind tunnel.

A measuring cylinder 3 is provided on a floor 1 of a building, which is horizontally supported by a gate-shaped column 2 erected at a predetermined interval, and the floor 1 near the upstream end of the measuring cylinder 3 is provided. A cart moving rail 4 extending in the width direction of the measuring cylinder 3 is laid, and a stratified cart 5 and a high-speed cart 6 are movably provided on the cart moving rail 4. To be connected to the upstream end of the measuring cylinder 3.

For example, in FIG. 4, a stratification cart 5 is selected so that a normal temperature stratification test can be performed.

As shown in FIG. 5, the stratified cart 5 is internally partitioned into a plurality of (approximately 30 to 40) stratified spaces 27 up and down by a plurality of horizontal partition plates 26. Air heater 2 extending in the width direction of the measuring cylinder 3
8 are provided so that the air flow introduced from the upstream side can flow to the downstream side as a stratified flow having a predetermined temperature distribution in the vertical direction.

Incidentally, in order to be able to cope with a test using such a high-speed airflow that does not require a stratified flow, a high-speed cart 6 having a small flow path resistance is prepared. It can be used.

[0007] Further, on the upstream side of the stratified cart 5, a contraction cylinder 7 and a rectifying cylinder 8 are connected, and a direction parallel to the measuring cylinder 3 provided on the upper floor 9 of the building. The upstream of the straightening cylinder 8 is connected to the circulation duct 10 extending through the fourth corner cylinder 11 and the third corner cylinder 12, and the axial blower 13 is connected to the upstream end of the circulation duct 10. ing. An intake cylinder 15 is connected to an intake side of the axial blower 13 via a heat exchanger cylinder 14.

A downstream cylinder 16 is connected to a downstream end of the measuring cylinder 3. A second corner cylinder is provided downstream of the downstream cylinder 16 via a first corner cylinder 17 and an airflow mixing cylinder 18. 19
The downstream end of the second corner cylinder 19 is connected to the end of the intake cylinder 15, and the exhaust cylinder 20 is provided on the side surface.

Below the measuring cylinder 3, a plurality of floor temperature adjusting units 2 for controlling the floor temperature of the measuring cylinder 3 are provided.
A plurality of hot air generators 22 for controlling the ceiling temperature of the measuring cylinder 3 are provided on the upper surface of the measuring cylinder 3.
Is arranged.

On the side surface of the measuring cylinder 3, there are provided an observation window 23, a worker entrance 24, a model loading door 25, and the like.

In the above configuration, when the axial blower 13 is operated, the air sucked from the intake body 15 is subjected to heat exchange inside the heat exchanger body 14 to be adjusted in temperature, and the air is blown by the axial blower 13. Circulating duct 10
Through the third corner cylinder 12 and the fourth corner cylinder 11, the flow is rectified in the rectifying cylinder 8, passes through the contraction cylinder 7, and is vertically divided by a multiplicity of horizontal partition plates 26 of the stratified cart 5. (Approximately 30 steps to 40 steps) into the stratified space 27, and in each stratified space 27, the airflow heater 2 extending in the width direction of the measuring cylinder 3.
8 are heated to different temperatures to form a stratified flow having a predetermined temperature distribution in the vertical direction, introduced into the inside of the measuring cylinder 3, and used for various wind tunnel experiments.

Here, the stratified flow is provided with a temperature distribution such that the temperature gradually increases from the lower layer toward the upper layer,
With such a temperature distribution, a stable stratified flow in which a secondary flow due to convection hardly occurs is obtained.

Further, the floor of the measuring cylinder 3 is cooled by a floor temperature adjusting unit 21 provided below the measuring cylinder 3, and the lower layer flow of the stratified flow having a relatively low temperature receives heat from the floor. To avoid secondary updrafts.

A hot air generator 2 provided on the upper surface of the measuring cylinder 3
The upper part of the stratified flow, which is heated at a relatively high temperature, is prevented from being deprived of heat by the ceiling part to generate a secondary downdraft.

The air that has passed through the measuring cylinder 3 is
6, is discharged from the exhaust cylinder 20 to the outside of the wind tunnel via the first corner cylinder 17, the airflow mixing cylinder 18, and the second corner cylinder 19;
Alternatively, it is formed so as to be circulated to the intake cylinder 15.

The temperature stratified wind tunnel is not limited to a stratified flow having a temperature distribution in which the temperature gradually increases from the lower layer to the upper layer. In some cases, the air may be circulated, or the entire cooled air flow may be circulated.

[0017]

However, the above-described conventional thermal stratified wind tunnel has the following problems.

That is, the multi-layer stratified space 27 of the stratified cart 5
Each airflow heater 28 disposed in the
Is provided so as to be uniformly heated in the width direction. However, since the stratified cart 5 has a side wall, heat is taken away by the side wall.

Incidentally, the side wall of the stratified cart 5 is provided with a heat insulating means. Even if the heat insulating means is provided, it is inevitable that a certain amount of heat is taken away by the side wall.

Then, the temperature of the side wall portion of the stratified cart 5 is slightly lower than that of the intermediate portion, and the outlet portion of the stratified cart 5, that is, the inlet portion of the measuring cylinder 3, as shown in the isothermal curve of FIG. The temperature distribution is not uniform in the width direction (since the temperature of the side wall portion of the stratified cart 5 is lower than that of the middle portion, the side wall portion of the stratified cart 5 is inclined upward as an isothermal curve), This causes the secondary flow a as shown in FIG. 7 to be caused in the downstream measuring cylinder 3.

The present invention has been made in view of the above circumstances, and provides a method and an apparatus for uniformizing a temperature distribution in a stratified flow width direction of a temperature stratified wind tunnel in which a stratified flow having a uniform temperature distribution in a width direction can be generated. The purpose is to do so.

[0022]

According to the present invention, a stratified cart 5 is provided.
Boundary layer adjusting device 2 provided on both sides of upstream contraction drum 7
9 is used to enlarge the boundary layer 40 formed on the side wall portion of the stratified cart 5 so as to improve heat collection in the boundary layer 40 portion where the wind speed is lower than that in the central portion, thereby forming a layer. The present invention relates to a method for equalizing the temperature distribution in the laminar flow width direction of the temperature-stratified wind tunnel, which comprises raising the temperature of the side wall portion of the cart 5 and uniforming the temperature distribution in the laminar flow direction.

In this case, the angle adjusting mechanism 33 of the boundary layer adjusting device 29 is operated to adjust the angle of the boundary layer adjusting plate 32 with respect to the contraction drum 7, so that the angle is formed on the side wall of the stratified cart 5. The boundary layer 40 may be enlarged.

Further, according to the present invention, in the temperature stratified wind tunnel in which the wind entering from the contraction drum 7 is formed into a stratified flow by the stratification cart 5 and sent to the measuring cylinder 3, the inlet of the stratification cart 5 of the contraction drum 7 is provided. The present invention relates to a device for equalizing a temperature distribution in a stratified flow width direction of a temperature stratified wind tunnel, wherein boundary layer adjusting devices 29 are attached to both side positions.

In this case, the boundary layer adjusting device 29
Is a boundary layer adjusting plate 32 whose upper end is pivotally attached to the contraction drum 7 by a hinge portion 31 and whose angle can be adjusted in the horizontal direction.
And an angle adjusting mechanism 33 for adjusting the angle of the boundary layer adjusting plate 32 with respect to the contraction drum 7.

According to the above means, the following effects can be obtained.

In general, when there is a wind flow along a wall,
The wind speed is constant at a distance from the wall, but near the wall,
The wind speed decreases as you approach the wall. The portion where the wind speed becomes slower than a certain value is called a boundary layer 40.

Since the wind speed of the boundary layer 40 is reduced as described above, in the stratified cart 5, the wind passes through the boundary layer 40 more than the central portion, and accordingly, the boundary layer 40 The portion 40 has improved heat collection.

However, since the boundary layer 40 is usually narrow, the improvement of heat collection by the boundary layer 40 does not significantly affect the temperature uniformity of the stratified flow in the width direction.

Therefore, in the present invention, the heat collection is improved by attaching the boundary layer adjusting device 29 to both sides of the inlet of the stratified cart 5 of the contraction drum 7, and expanding the boundary layer 40 by the boundary layer adjusting device 29. In this case, the temperature distribution of the stratified flow is made uniform in the width direction.

That is, by operating the angle adjusting mechanism 33, the boundary layer adjusting plate 32 is rotated by a required amount in the horizontal direction about the shaft 30 extending in the vertical direction of the hinge 31, and
The boundary layer adjusting plate 32 has a certain angle with respect to the contraction drum 7, and a large gap is formed between the downstream edge of the boundary layer adjusting plate 32 and the contraction drum 7.

As described above, when a gap is formed between the downstream edge of the boundary layer adjusting plate 32 and the contraction drum 7, a separation vortex 39 is formed downstream of the boundary layer adjusting plate 32. Become so.

When the separation vortex 39 is present on the upstream side, the downstream portion of the separation vortex 39 has a low wind speed, so that the entire downstream portion of the separation vortex 39 becomes the boundary layer 40 and the separation vortex 39 is formed. The boundary layer 40 is enlarged as compared with the case where there is no.

As described above, when the boundary layer 40 is enlarged,
As described above, the portion of the stratified cart 5 near the side wall in each of the stratified spaces 27 where the heat collection is improved is increased, and the portion of the stratified cart 5 near the side wall of each stratified space 27 is increased due to the increase in the portion where the heat collection is improved. The temperature will be raised.

Therefore, by setting the angle of the boundary layer adjusting plate 32 to the contraction drum 7 at an optimum angle, the temperature distribution of the stratified flow can be made uniform in the width direction.

[0036]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of the present invention.

Regarding the basic configuration of the temperature stratified wind tunnel,
3 to 5, the same portions are denoted by the same reference numerals and description thereof will be omitted.

In the present invention, the boundary layer adjusting device 29 is mounted on both sides of the inlet of the stratification cart 5 of the contraction drum 7.

The boundary layer adjusting device 29 is provided with a boundary layer adjusting plate 32 having an upstream end side pivotally attached to the flow contractor 7 and having a horizontally adjustable angle by a hinge portion 31 having a shaft 30 extending vertically. And an angle adjustment mechanism 33 for adjusting the angle of the boundary layer adjustment plate 32.

The angle adjusting mechanism 33 may be of any type. For example, the angle adjusting mechanism 33 penetrates the contraction cylinder 7, has a handle 34 on the outer end side, and has a slide member 35 on the inner end side. An operation rod 36 pivotally supported by the boundary layer adjustment plate 32 in a horizontal direction through the operation rod 36, and is attached to a penetrating portion of the operation rod 36 with respect to the contraction cylinder 7, so that the operation rod 36 is moved by a tightening screw 37. It is composed of a rod insertion support ring 38 fixed.

In the figure, reference numeral 39 denotes a separation vortex formed downstream of the boundary layer adjusting plate 32, and reference numeral 40 denotes a boundary layer formed along the side wall of the measuring cylinder 3.

In the above configuration, the process of forming a stratified flow in the temperature stratified wind tunnel is the same as in FIGS.

The airflow heaters 28 arranged in the multi-layer stratified space 27 of the stratified cart 5 are provided so as to uniformly heat each stratified space 27 in the width direction. In addition, since the stratified cart 5 has a side wall, even if the side wall is provided with a heat insulating means, it cannot be avoided that a certain amount of heat is taken from the side wall, whereby the temperature distribution of the stratified flow is reduced in the width direction. The fact that there is a possibility of non-uniformity is as described above.

Therefore, in the present invention, the following is performed.

First, in general, when there is a flow of wind along a wall, the wind speed is constant at a position distant from the wall. However, near the wall, the wind speed decreases as approaching the wall. Such a portion where the wind speed becomes slower than a certain value is called a boundary layer 40.

Since the boundary layer 40 has a low wind speed as described above, each stratified space 27 of the stratified cart 5
In this case, the wind has a longer passage time in the boundary layer 40 than in the central portion, and accordingly, the heat in the boundary layer 40 is better.

However, since the boundary layer 40 is usually narrow, the improvement in heat collection by the boundary layer 40 does not significantly affect the temperature uniformity of the stratified flow in the width direction.

Therefore, in the present invention, the heat collection is improved by mounting the boundary layer adjusting device 29 at both sides of the inlet of the stratification cart 5 of the contraction drum 7, and expanding the boundary layer 40 by the boundary layer adjusting device 29. In this case, the temperature distribution of the stratified flow is made uniform in the width direction.

That is, the tightening screw 37 of the rod insertion support ring 38 in the angle adjusting mechanism 33 is loosened, and the operating rod 36 is pressed by grasping the handle 34.
6 into the contraction drum 7 by a required amount.
By tightening 7, the position of the operation rod 36 is fixed in a pushed state.

Then, the boundary layer adjusting plate 32 is rotated in the horizontal direction by a required amount about the axis 30 extending in the vertical direction of the hinge portion 31, and the boundary layer adjusting plate 32 is turned at a certain angle with respect to the contraction drum 7. As a result, a large gap is formed between the downstream end of the boundary layer adjusting plate 32 and the contraction drum 7.

As described above, when a gap is formed between the downstream end of the boundary layer adjusting plate 32 and the flow reducing cylinder 7, the downstream side of the boundary layer adjusting plate 32 as shown in FIG. , A separation vortex 39 is formed.

If there is a separation vortex 39 on the upstream side, the downstream portion of the separation vortex 39 has a low wind speed, so that the entire downstream portion of the separation vortex 39 becomes the boundary layer 40, and the separation vortex 39 The boundary layer 40 is enlarged as compared with the case where there is no.

As described above, when the boundary layer 40 is enlarged,
As described above, the portion of the stratified cart 5 near the side wall in each of the stratified spaces 27 where the heat collection is improved is increased, and the portion of the stratified cart 5 near the side wall of each stratified space 27 is increased due to the increase in the portion where the heat collection is improved. The temperature will be raised.

Therefore, by setting the angle of the boundary layer adjusting plate 32 with respect to the contraction drum 7 to an optimum angle, the temperature distribution of the stratified flow is made uniform in the width direction as shown in FIG. Will be able to

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0057]

As described above, according to the method and apparatus for uniformizing the temperature distribution in the stratified flow width direction of the temperature stratified wind tunnel of the present invention, it is possible to generate a stratified flow having a uniform temperature distribution in the width direction. An excellent effect that it can be achieved.

[Brief description of the drawings]

FIG. 1 is a partially enlarged plan view showing a partly broken portion according to an example of an embodiment of the present invention.

FIG. 2 is a temperature distribution diagram when FIG. 1 is viewed from the direction of arrows II-II.

FIG. 3 is a side view schematically showing an example of a conventional temperature stratified wind tunnel.

4 is a view taken in the direction of arrows IV-IV in FIG. 3;

FIG. 5 is a schematic perspective view of the stratified cart in FIG. 4 as seen through;

FIG. 6 is a temperature distribution diagram when FIG. 5 is viewed from the direction of arrows VI-VI.

FIG. 7 is a diagram showing a state of a secondary flow when FIG. 5 is viewed from the direction of arrows VII-VII.

[Explanation of symbols]

 Reference Signs List 3 measuring cylinder 5 stratified cart 7 contraction drum 29 boundary layer adjusting device 31 hinge part 32 boundary layer adjusting plate 33 angle adjusting mechanism part 40 boundary layer

Claims (4)

[Claims] 1. A stratification cart (5) upstream of a contraction drum (7)
Using the boundary layer adjustment devices (29) provided at both sides of the
The boundary layer (4) formed on the side wall of the stratified cart (5)
By increasing the temperature of the side wall portion of the stratified cart (5) by enlarging the temperature of the side wall portion of the stratified cart (5) by enlarging the boundary layer (40) where the wind speed is lower than that of the central portion, the temperature is increased. A method for equalizing a temperature distribution in a stratified flow width direction of a temperature stratified wind tunnel, characterized by equalizing a flow temperature distribution in a width direction. 2. The stratified cart (3) is operated by operating the angle adjusting mechanism (33) of the boundary layer adjusting device (29) to adjust the angle of the boundary layer adjusting plate (32) with respect to the contraction drum (7). The method of claim 1, wherein the boundary layer (40) formed on the side wall portion of (5) is enlarged. 3. A stratified cart of a contraction drum (7) in a temperature stratified wind tunnel in which wind entering from a contraction drum (7) is converted into a stratified flow by a stratification cart (5) and sent to a measurement cylinder (3). (5)
An apparatus for equalizing the temperature distribution in a stratified flow width direction of a temperature stratified wind tunnel, wherein boundary layer adjusting devices (29) are attached to both sides of an inlet portion. 4. A boundary-layer adjusting plate (32), which is capable of adjusting an angle in the horizontal direction, having an upstream end pivotally connected to a contraction drum (7) by a hinge portion (31). )
4. The temperature distribution in the stratified flow width direction of the temperature stratified wind tunnel according to claim 3, comprising: an angle adjusting mechanism (33) for adjusting an angle of the boundary layer adjusting plate (32) with respect to the contraction drum (7). Uniform device.