JP3476063B2 - Heat exchanger - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger composed of a perforated flat metal tube having a large number of pores inside a tape-shaped metal plate.

[0002]

2. Description of the Related Art A Stirling refrigerator is drawing attention as a refrigerator that generates cold heat without using Freon. This is a structure in which heat and cold are generated by the reciprocating motion of the piston in a cylindrical structure such as a cylinder. That is, it is important to efficiently transport heat from the cylindrical structure that serves as a heat source in order to improve the performance of the Stirling refrigerator.

In order to transport the heat from the cylindrical heat source, when the heat is taken out from the side surface of the cylindrical heat source, a heat exchanger in which fins are radially attached to an annular material that closely adheres to the side surface or a fin in a strip shape is attached. There is a method using an exchanger. It is also possible to attach a jacket to the heat source and flow a heat medium in the jacket to transport heat.

Further, as a means for efficiently transporting heat from a cylindrical heat source, there is a method of winding a thin tube heat pipe around the side surface of a cylinder.

[0005]

As the finned annular heat exchanger described above, a light metal material having flexibility such as aluminum which is press-extruded is often used. However, its shape is restricted because it is press extrusion.

Further, in order to improve the thermal efficiency in the limited space, it is necessary to increase the heat transfer area. Since the heat exchanger has a large number of fins composed of a large number of layers and ventilates between the fins, further increasing the number of fins increases the pressure loss of the air flow passing between the fins, resulting in a stronger force. A blower is required. In addition, since heat may not be sufficiently transmitted to the ends of the fins, it is actually difficult to improve the thermal efficiency.

Further, also in the method of attaching a jacket to the cylindrical heat source and flowing the heat medium in the jacket, it is necessary to increase the fins inside the jacket to increase the heat transfer area. Therefore, the flow resistance of the heat medium increases, and it is necessary to increase the capacity of the circulation pump for circulating the heat medium. Furthermore, since the jacket method needs to pay attention to measures against leakage of the liquid heat medium, the structure is more complicated than the air cooling method in which heat is transferred by applying air, and as a result, the production cost of the system tends to increase.

When the thin tube heat pipe is wound around the side surface of the cylindrical heat source, it is necessary to provide an annular member made of an aluminum thin plate or the like in the heat radiating portion. In addition, the performance of the heat exchanger changes depending on the winding direction of the thin tube heat pipe, which causes a restriction on the directionality.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a heat exchanger that efficiently transfers heat from the side surface of a cylindrical heat source with a simple and inexpensive structure.

[0010]

In order to achieve the above object, the heat exchanger of the present invention comprises a flat, perforated flat metal tube having therein a large number of long pores arranged in parallel with each other.
In a heat exchanger in which the working fluid is enclosed in the pores, the perforated flat metal tube has a side surface that defines an arc with a small diameter and a circle with a large diameter.
Side with an arc and a small diameter Side with an arc and a large diameter
Cylindrical body consisting of a short side that connects to the side that defines the arc
Formed into a hollow body with a circular cross section at the center using multiple cylinders
To form a hollow cylindrical shape.
A heat source is attached to the perforated flat metal tube while closely contacting it.

The porous flat metal tube is obtained in one step by press extrusion of a metal, particularly a light metal such as aluminum or magnesium, and has a large number of long pores arranged in parallel with each other inside and a flat appearance. I'm in a shape. Both ends of this perforated flat metal tube are processed to form pores into a sealed tunnel, and a plate-type heat pipe is formed by vacuum-sealing the working liquid in an amount less than the volume of the tunnel. This heat pipe corresponds to several tens of turns of the thin tube in the meandering thin tube heat pipe, and is provided at a lower cost than the meandering thin tube heat pipe for both material cost and assembly cost.

The heat exchanger using the porous flat metal tube has the same principle as the meandering thin tube heat pipe, and is different from the operation of the conventional heat pipe for phase change application of the two-phase condensable hydraulic fluid. That is, the working fluid in the pores always fills and closes the pores due to its surface tension, and vapor bubbles and droplets are alternately dispersed and arranged in the entire pores. When a pressure wave is generated by nucleate boiling of the working liquid in the heat receiving portion of the heat exchanger, the vapor bubbles and the liquid droplets vibrate in the axial direction, and this vibration transfers heat from the high temperature side to the low temperature side.

[0013]

[0014]

In each of the cylinders having the above structure, the heat generated by the heat source is conducted from the portion of the porous flat metal tube which is in close contact with the cylindrical heat source to the end side which is not in close contact. As a result, in each cylinder, the heat exchanged with the hollow air in the cylinder is conducted.

Another heat exchanger of the present invention comprises a flat, perforated flat metal tube having a large number of long pores arranged in parallel with each other, and a working fluid is enclosed in the pores. In a container, a perforated flat metal tube is formed into an arc shape with a concentric cross section.
A molded body having a shape meandering several times along it is formed, and a plurality of the molded bodies are combined so as to form a hollow having a circular cross section in the center, and the hollow cylindrical heat source is the porous flat metal. A heat exchanger characterized by being mounted in close contact with a pipe.

In each of the molded products having the above structure, the heat generated by the heat source is conducted from the portion of the porous flat metal tube which is in close contact with the cylindrical heat source to the end which is not in close contact. Then, the air between the porous flat metal tubes of each molded body is heat-exchanged with the conducted heat. At this time, in the porous flat metal tube 1, heat is sufficiently conducted to the farthest portion from the cylindrical heat source,
There, the heat is exchanged with the air, which is the same as the portion close to the cylindrical heat source.

Further, the present invention is characterized in that corrugated fins are inserted between the opposed porous flat metal tubes. This increases the heat transfer area of the heat exchanger.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First, the porous flat metal tube used in each embodiment will be described. Figure 1 is a block diagram of a perforated flat metal tube. (A) is a front view, (b) is the same figure
It is a sectional view taken along the line AA ′ in (a). As shown in the figure, pores 2 are provided inside the porous flat metal tube 1.

Immediately after processing by press extrusion molding, the pores 2 penetrate in the length direction of the metal tube 1 from the end portion 1a to the end portion 1b of the porous flat metal tube 1. By connecting both ends of these through pores to the ends of the adjacent through pores, one serpentine pore 2 is formed as shown in the figure. The working fluid in an amount less than the internal volume is vacuum-sealed in the pores 2.

A first embodiment according to the present invention will be described. FIG. 2 is a diagram showing the heat exchanger. The heat exchanger has a substantially cylindrical outer shape, and FIG. 2 shows a cross section taken along a plane perpendicular to the axial direction of the heat exchanger. As shown in the figure, the heat exchanger 3 of the present embodiment is one in which the porous flat metal tube 1 is formed so that its cross section becomes spiral.

A cylindrical heat source 4 is mounted at the center of the spiral of the heat exchanger 3. The end 1a of the porous flat metal tube 1 is located at the center of the spiral, and the end 1b is located at the outermost side. The perforated flat metal tube 1 is wound around the side surface of the heat source 4 on the end 1a side, and the spiral is started from the outside.

According to the heat exchanger having the above structure, the heat generated by the heat source 4 is transported from the portion including the end portion 1a of the porous flat metal tube 1 in close contact with the heat source 4 to the end portion 1b side. And this heat exchanges heat with the air in the space 5 between the facing porous flat metal tubes 1. In particular, since the porous flat metal tube 1 is in close contact with the side surface of the heat source 4, the heat generated by the heat source 4 is transported to the end 1b side without waste.

The heat exchanger 3 is blown by a blower (not shown), and an air flow passes through the space 5 along the axial direction of the heat exchanger 3. Therefore, this air flow efficiently exchanges the heat of the perforated flat metal tube 1. Also, the heat source 4
The heat from the can be transported to a predetermined place through a duct or the like.

The configuration of the present invention is not limited to the embodiment shown in FIG. 2, but the desired heat transfer area can be obtained by adjusting the number of spirals of the perforated flat metal tube 1 and the interval between the perforated flat metal tubes 1. Also, the size of the heat exchanger 3 can be set.

Next, a second embodiment according to the present invention will be described. FIG. 3 is a view showing the heat exchanger and corresponds to FIG. 2 of the first embodiment. As shown in the figure, the heat exchanger 3 of the present embodiment is a combination of two cylinders 6 made of a perforated flat metal tube 1. The cylindrical body 6 is formed so that its cross section has a semicircular shape. The end 1a of the porous flat metal tube 1 is located on the side surface that encloses the arc having the smaller diameter, and the end 1b is close to the end 1a.

In the heat exchanger 3 of this embodiment, the cylindrical body 6 is
One is a combination of the smaller arcs, with the sides facing each other, and a space with a circular cross section is formed in the center. A cylindrical heat source 4 is mounted in this hollow, and the side surface of the heat source 4 is in close contact with the side surface of the heat exchanger 3.

According to the heat exchanger 3 having the above structure, the heat generated by the heat source 4 is generated by the heat source 4 including the end 1a of the porous flat metal tube 1.
Is transported to the end 1b side from the portion in close contact with. And
Heat exchange is performed with the air in the hollow 5 of each cylindrical body 6. In particular, since the porous flat metal tube 1 is in close contact with the side surface of the heat source 4, the heat generated by the heat source 4 is transported to the end 1b side without waste.

As described above, the heat exchanger 3 of this embodiment is
As in the first embodiment, the air can be efficiently transported by ventilating the hollows 5 of the respective cylinders 6. In the present embodiment, the heat exchanger 3 is configured by the two tubular bodies 6, but the heat exchanger 3 may be further divided to configure the heat exchanger by three or more tubular bodies. Since the area of the rectangular side surface (side surface 6a in FIG. 3) connected to the side surface that encloses the smaller arc and the side surface that defines the larger arc increases by the number of cylinders, the heat transfer area also increases. The heat exchange efficiency is further improved.

Next, a third embodiment according to the present invention will be described. FIG. 4 is a view showing the heat exchanger and corresponds to FIG. 2 of the first embodiment. As shown in the figure, the heat exchanger 3 of the present embodiment is a combination of two molded bodies 7 made of the porous flat metal tube 1. The molded body 7 has a substantially semi-cylindrical shape, and its cross section has a shape in which the porous flat metal tube 1 meanders along each semi-circular arc of three concentric circles. The end portion 1a of the porous flat metal tube 1 is located on the side surface that encloses the arc having the smallest diameter, and the end portion 1b is located on the side surface that encloses the arc having the largest diameter.

In the heat exchanger of this embodiment, the molded body 7 is
The smallest circular arc is combined so that the side faces facing each other face each other, and a space with a circular cross section is formed at the center thereof. The cylindrical heat source 4 is mounted in this space, and the side surface of the heat source 4 is in close contact with the side surface of the heat exchanger 3.

According to the heat exchanger having the above-mentioned structure, the heat generated by the heat source 4 is transported from the portion close to the heat source 4 including the end portion 1a of the porous flat metal tube 1 to the end portion 1b side. And this heat exchanges heat with the air in the space 5 between the facing porous flat metal tubes 1. In particular, since the porous flat metal tube 1 is in close contact with the side surface of the heat source, the heat generated by the heat source is transported to the end 1b side without waste.

As described above, the heat exchanger 3 of this embodiment is
By ventilating the space 5 as in the first embodiment, heat can be efficiently transported. The configuration of the present invention is not limited to the embodiment shown in FIG. 4, but the desired heat transfer area and the size of the heat exchanger 3 can be obtained by adjusting the number of meandering of the perforated flat metal tube 1 and the interval thereof. Can be

5 to 7 show still another embodiment. In these heat exchangers, corrugated fins 8 are inserted into the spaces 5 between the facing porous flat metal tubes 1 in the respective embodiments of the first to third embodiments. As a result, the heat transfer area is increased, so that the heat exchange efficiency is further improved.

The porous flat metal tube 1 used in each of the above embodiments is not limited to that shown in FIG. 1 and may have any shape.

[0036]

As described above, the heat exchanger of the present invention is composed of a perforated flat metal tube and secures a heat transfer area of a sufficient size without using fins. Therefore, heat can be efficiently transported from the side surface of the cylindrical heat source with an inexpensive structure. In particular, it can be constructed at a lower cost than a thin tube heat pipe.

Furthermore, by mounting the corrugated fins, the heat transfer area is further increased and the heat exchange efficiency is further improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a porous flat metal tube used in the present invention.

FIG. 2 is a cross-sectional view of the heat exchanger of the first embodiment according to the present invention.

FIG. 3 is a sectional view of a heat exchanger of a second embodiment according to the present invention.

FIG. 4 is a cross-sectional view of a heat exchanger of a third embodiment according to the present invention.

FIG. 5 is a cross-sectional view of a heat exchanger of another embodiment according to the present invention.

FIG. 6 is a cross-sectional view of a heat exchanger of another embodiment according to the present invention.

FIG. 7 is a cross-sectional view of a heat exchanger of another embodiment according to the present invention.

[Explanation of symbols]

1 Perforated flat metal tube 2 pores 3 heat exchanger 4 cylindrical heat source 5 spaces 6 cylinder 7 molded 8 corrugated fins

Continuation of the front page (56) Reference JP-A-9-303983 (JP, A) JP-A-9-14875 (JP, A) JP-A-9-321197 (JP, A) JP-A-57-2987 (JP , A) Actually open 3-26084 (JP, U) Actually open 63-104862 (JP, U) Actually open 63-179464 (JP, U) Actually open 63-197974 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) F28F 1/02 F28D 1/047

Claims (3)

(57) [Claims] 1. A large number of long pores arranged parallel to each other inside
Consisting of a flat, perforated flat metal tube with
In the heat exchanger in which the working fluid is enclosed, the perforated flat metal tube has a side surface and a diameter
Sides drawing a large arc and sides drawing a small arc
And the side of the short shape that is continuous with the side surface that describes the large-diameter circular arc
It is formed in a cylindrical body composed of
It is a combination that has a hollow cross section.
The hollow cylindrical heat source closely contacts the perforated flat metal tube.
A heat exchanger characterized by being installed while. 2. A large number of long pores arranged parallel to each other inside
Consisting of a flat, perforated flat metal tube with
In the heat exchanger filled with the working fluid, the porous flat metal tube has several sections along the arc of a concentric circle.
Form a molded body in a meandering shape and use multiple molded bodies
And combined to form a hollow with a circular cross section in the center
The hollow cylindrical heat source is the porous flat metal
Heat exchange characterized by being closely attached to the metal pipe
vessel. 3. Between the opposed flat metal pipes facing each other
A corrugated fin is inserted in the
The heat exchanger according to claim 1 or claim 2.