JPH06207756A - Vortex tube - Google Patents

Abstract

(57) [Abstract] [Purpose] The heat separation efficiency of compressed air can be improved, and even if the tube length of the tube main body is shortened, the heat separation performance does not decrease. Therefore, the cooling performance is improved and the cooling capacity is maintained. We provide a vortex tube that can be made compact and lightweight while still being applicable to heat sinks of high-speed aircraft. [Structure] A nozzle for ejecting pressurized air from a tangential direction and a low temperature air outlet in the axial direction are provided at one end of a cylindrical tube body, and a conical flow rate adjusting valve and a high temperature air outlet are provided at the other end. In the vortex tube, a flow control disk is placed in the center before the hot air outlet, and the flow at the center is shut off to ensure that only hot air flows in the annular portion along the inner surface of the tube body. A vortex tube characterized by being made to flow.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a vortex tube which can be applied, for example, as a heat sink of an aircraft, especially as a cooling device of a high speed aircraft.

[0002]

2. Description of the Related Art As shown in FIG. 6, a vortex tube has a nozzle 2 for ejecting pressurized air from a tangential direction into the tube body 1 and a low temperature air outlet in the axial direction at one end of a cylindrical tube body 1. 3 and a conical flow valve 4 and a hot air outlet 5 at the other end, which has the function of separating the thermal energy of the pressurized air into high temperature and low temperature (an example of a vortex tube). As JP-A-4
There is 7-25739. ).

By the way, this vortex tube has a simple structure because it does not have a rotating part, and there is no fear of wear or failure. However, in order to exert the heat separation function, a large length is taken with respect to the tube diameter. Since it is necessary, there are great restrictions on the placement.

On the other hand, the fact is that the heat separation efficiency does not increase so much even if the length is made much larger than the tube diameter.

For this reason, most of the studies on vortex tubes so far have focused on improving the heat separation efficiency and shortening the tubes.

However, in many cases, the shape is changed and the dimensions are specified, and the structure is complicated, but the desired result is not obtained.

[0007]

Therefore, the present inventors
The thermal separation in the basic vortex tube 6 shown in FIG. 7 was reexamined.

The heat flow region in the vortex tube 6 is described in Takahama's paper (Journal of the Japan Society of Mechanical Engineers, Volume 68, 560, No. 1).
255 “Energy Separation of Gas by Vortex Tube”), it is composed of two flow fields, a swirling flow field A at high compression temperature and a reverse flow field B at low expansion temperature, and the boundary of the flow field is as shown by the dotted line. It is shown.

The length L of the tube body 1 and the tube body 1
In relation to the inner diameter D of the swirl flow field A and the reverse flow field B
Boundary region γ _{s of} is shown in FIG. 8, and when it is shown on an L / D basis, it becomes as shown in FIG. Γ _w is the vortex
It is the inner radius of the tube 6. According to FIG. 8, the boundary area γ
_s shows the position of υ _L = 0 and also shows the sudden damping point of υ _θ (outer edge of the jet flow).

The influence on the boundary region γ _s is shown in the paper of Takahama, and when these are formulated, it is given by the following equation. γ _s / γ _w = -0.00847 × (L / D) +0.572+ (ξ-0.5) × 0.2 ...... (1) (ξ: Low temperature air flow rate / Supply air flow rate)

Ν _θ / υ _m , υ _L / υ in the high temperature region of FIG.
The maximum value of _m is shown in FIG. (Υ _L : axial component,
υ _θ : circumferential component, υ _m : nozzle jet velocity)

As is apparent from FIG. 10, after L / D-5.0, although there is friction damping from the wall surface, the high temperature region can be regarded as a swirling flow field A of uniform diffusion. Therefore, L /
After D to 5.0, heat separation is performed, but at the same time, heat diffusion such as heat transfer is performed in an integrated effect, so that the separation of the high temperature and low temperature flow fields A and B at this position improves cooling performance. Is necessary for.

The present invention aims to improve the cooling performance of the vortex tube and shorten the pipeline of the vortex tube while maintaining the cooling capacity, focusing on the above points.

[0014]

A vortex tube of the present invention for solving the above-mentioned problems is a nozzle for ejecting pressurized air from a tangential direction to one end of a cylindrical tube body and a low temperature air in the axial direction. A vortex with an outlet and a conical flow control valve and hot air outlet at the other end.
In the tube, a flow control disk is placed in the center before the hot air outlet, and the flow at the center is blocked so that only the hot air flows in the annular part along the inner surface of the tube body. It is characterized by having done.

[0015]

As described above, in the vortex tube of the present invention, the flow control disk is arranged in the center part in front of the high temperature air outlet, and the flow at the center part is cut off to form a circle along the inner surface of the tube body. Since only hot air flows in the annular part, the boundary between the swirling flow field of high temperature air and the reverse flow field of low temperature air is less likely to be swirled near the hot air outlet, and therefore low temperature air Is not drawn into the swirling flow of high temperature air and improves the heat separation efficiency of the compressed air. Even if the tube length of the tube body is shortened, the heat separation performance does not decrease, and the size and weight are reduced. Is possible.

[0016]

EXAMPLE An example of the vortex tube of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes a cylindrical tube body, which is provided with a nozzle 2 for ejecting pressurized air into the tube body 1 from a tangential direction at one end and a low temperature air outlet 3 having a small diameter in the axial direction. At the other end of the tube body 1, a conical flow rate adjusting valve 4 and a hot air outlet 5 are provided.
However, a flow control disc 7 is arranged in the center of the hot air outlet 5 in front of the hot air outlet 5 to block the flow at the center, and only the hot air is collected at the annular portion 8 along the inner surface of the tube body 1. It's flowing.

FIG. 2 shows the vortex tube 6'of FIG.
FIG. 4 is an exploded perspective view of the flow control disc 7, in which the annular portion 8 in which only the high temperature air flows is a honeycomb porous plate 9, but the present invention is not limited to this. As shown in FIG. 3, the mounting arm 1 is provided around the flow control disk 7.
0 may be provided so that the space between the mounting arms 10 becomes an annular portion 8'where only high temperature air flows. The flow control disc 7 may be configured to move forward and backward according to the flow rate ratio.

In the vortex tube 6'having the above structure, the relationship between the length L of the tube body 1 and the inner diameter D of the tube body 1 is L / D = 4, L / D = 9, L / D = 1
When the heat separation performance in relation to the flow rate ratio when 9 was tested, the results shown in the graph of FIG. 4 were obtained. In addition, in the conventional vortex tube 6 shown in the figure having no flow control disc, the relationship between the length L of the tube body 1 and the inner diameter D of the tube body 1 is L / D =
4, when L / D = 9 and L / D = 19, the heat separation performance in relation to the flow rate ratio was tested, and the results shown in the graph of FIG. 5 were obtained.

As is clear from the comparison of FIGS. 4 and 5, the conventional vortex tube 6 having no flow control disk has a short length of the tube body 1 such as L / D = 4.
While the heat separation efficiency is low, the vortex tube 6'of the embodiment having the flow control disk 7 has the L / D of the conventional example even when the length of the tube body is short such as L / D = 4.
It can be seen that a heat separation efficiency as high as that of the vortex tube 6 of = 19 was obtained. Also, the tube body 1
The vortex tube 6'of the embodiment having the flow control disk 7 even when the lengths of L and D are as long as L / D = 19,
It can be seen that the heat separation efficiency is higher and more stable than the conventional vortex tube 6 which does not have the flow control disk 7.

Thus, the heat separation efficiency is high even if the length of the vortex tube 6'of the embodiment is short. The swirling flow field A of high temperature air and the reverse flow of low temperature air are due to the existence of the flow control disk 7. Since the boundary with the flow field B of No. 2 is not easily swirled near the high temperature air outlet 5, the low temperature air is not drawn into the swirl flow of the high temperature air and flows, and the heat separation efficiency of the compressed air is improved. It is none other than.

[0021]

As described above, according to the vortex tube of the present invention, the heat separation efficiency of the compressed air can be improved, and the heat separation performance is not deteriorated even if the tube length of the tube body is shortened. The vortex tube can be made smaller and lighter while improving the cooling performance and maintaining the cooling capacity, and can be applied to the heat sink of high-speed aircraft.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of a vortex tube of the present invention.

2 is an exploded perspective view of the vortex tube of FIG. 1. FIG.

FIG. 3 is a view showing another example of the flow control disc in the vortex tube of the present invention.

FIG. 4 is a graph showing the results of a heat separation performance test in relation to the flow rate ratio of the vortex tube of the present invention.

FIG. 5 is a graph showing the results of a heat separation performance test in relation to the flow rate ratio of a conventional vortex tube.

FIG. 6 is a schematic vertical sectional view of a conventional vortex tube.

FIG. 7 is an explanatory diagram of a heat separation action of a conventional vortex tube.

FIG. 8 is a graph showing a boundary region γ _s between a swirling flow field A and a reverse flow field B in the relationship between the length L of the tube body and the inner diameter D of the tube body in the conventional vortex tube. .

9 is a graph showing the boundary region γ _s of FIG. 8 on an L / D basis.

FIG. 10 shows υ _θ / υ _m , υ _L / υ _{m in} the high temperature region of FIG.
It is a graph showing the maximum value of.

[Explanation of symbols]

 1 Tube Main Body 2 Nozzle 3 Low Temperature Air Outlet 4 Flow Control Valve 5 High Temperature Air Outlet 6'Vortex Tube 7 Flow Control Disc 8,8 'Annular Portion

Claims (1)

[Claims] 1. A cylindrical tube body has a nozzle for ejecting pressurized air from a tangential direction at one end and a low temperature air outlet in the axial direction, and a conical flow rate adjusting valve and a high temperature air outlet at the other end. In a vortex tube with a high temperature air outlet, a flow control disk is placed in the front center of the hot air outlet, and the flow at the center is cut off to prevent the hot air from flowing through the annular portion along the inner surface of the tube body. A vortex tube characterized by allowing only the flow.