GB2339893A - Heat exchanger with water absorbent covering - Google Patents

Description

2339893

HIGH PERFORMANCE EVAPORATIVE HEAT EXCHANGER BACKGROUND OF THE INVENTION

The present invention relates to a high performance evaporative heat exchanger for use in an air conditioning system or refrigerator, and more particularly to such a high performance evaporative heat exchanger which comprises a plurality of radiating fins with water absorptive covering means what absorb heat from heat conductive tubes and cooling water from a water supply source to make a heat exchange process.

The caoling of a regular air conditioner or refrigerator may be done by means of water or air. The water cooling method and the air cooling method still have drawbacks. The air cooling method is to achieve heat exchange by means of convection. However, this cooling method is less efficient, and suitable only for a small scale equipment such as a window mounting air conditioner or a home refrigerator. For a big scale air conditioning system or industrial refrigerator, a big scale cooling fan shall be used with a big scale condenser coil. This arrangement is expensive. Further, it consumes much energy, and produces high noise during operation.

The water cooling method i's-'to achieve heat exchange by cooling water. This method produces better effect, however it must be used with a cooling tower. When a cooling tower is installed, a I piping system must be arranged between the cooling tower and the air conditioning system. It is complicated and dangerous to construct a cooling tower and a piping system for an air conditioning system- SUMMARY OF THE INVENTION

The present invention has been accomplished to provide a high performance evaporative heat exchanger which eliminates the aforesaid drawbacks. It is one object of the present invention to provide a high performance evaporative heat exchanger for an air conditioning system or refrigerator which achieves high exchange ratio by evaporating I gram of water to absorb 539 calories It is another object of the present invention to provide a high performance evaporative heat exchanger for an air conditioning system or refrigerator which eliminates the installation of a cooling water tower and the related piping system. It is still another object of the present invention to provide a high performance evaporative heat exchanger which is inexpensive to manufacture. According to one aspect of the present invention, the high performance evaporative heat exchanger comprises a front end plate and a rear end plate connected in parallel, a plurality of radiating fins connected in parallel between the front end plate and the rear end plate, the radiating fins each comprising a metal sheet and a water 2 absorptive covering covered on the metal sheet, and a plurality of heat conductive tubes mounted in holes on the radiating fins and connected between the front end plate and the rear end plate, wherein cooling water is supplied to the water absorptive coverings of the radiating fins to absorb heat from the heat conductive tubes, and to be evaporated from the radiating fins. According to another aspect of the present invention, the water absorptive covering of each radiating fin can be covered on the whole surface of the respective metal sheet when used for making a full evaporative heat exchanger, or covered on a part of the respective metal sheet when used for making a partial evaporative heat exchanger.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure I is a perspective view of a high performance evaporative heat exchanger according to one embodiment of the present invention.

Figure 2 is a sectional view of in an enlarged scale of a part of the high performance evaporative heat exchanger shown in Figure Figure 2A is an enlarged view of a part of Figure 2 showing 20 the structure of the radiating fin, Figure 3 shows two alternate forms of the heat conductive tube according to the present invention.

3 Figure 4 shows radiating fins for a full evaporative type heat exchanger according to the present invention.

Figure 5 shows radiating fins for a partial evaporative type heat exchanger according to the present invention.

Figure 6 shows an application example of a full evaporative type heat exchanger according to the present invention.

Figure 7 shows another application example of a full evaporative type heat exchanger according to the present invention.

Figure 8 shows an application example of a full evaporative type heat exchanger according to the present invention.

Figure 9 shows another application example of a partial evaporative type heat exchanger according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to Figures 1 2, 2A and 3, a high performance evaporative heat exchanger in accordance with the present invention is generally comprised of front and rear end plates 2, a plurality of heat conductive tubes 3, and a plurality of radiating fins I (see Figure 1). The radiating fins I each are comprised of a metal sheet 4 and a water absorptive covering 5 covered on the metal sheet 4 (see Figures 2 and 2A). The heat conductive tubes 3 can be made in the form of a round tube 6 or flat tube with round ends 7 (see Figure 3). The radiating fins I are arranged in a stack and 4 connected between the front and rear end plates 2. The heat conductive tubes 3 are mounted in respective through holes on the end plates 2 and the radiating fins 1. The water absorptive coverings 5 of the radiating fins I absorb condensed water from the air conditioning system or refrigerator, enabling inside heat of the heat conductive tubes 3 to be absorbed by water in the water absorptive coverings 5 and then carried away from the radiating fins 1 into the air when water is evaporated.

Referring to Figures from 4 through 9 and Figures 2 and 2A again, the evaporative heat exchanger can be a full evaporative type heat exchanger 9 as shown in Figure 6 or 7, or a partial evaporative type heat exchanger 10 as shown in Figure 8 or 9. In a full evaporative type heat exchanger 9, the metal sheet 4 of every radiating fin I is completely covered within the respective water absorptive covering 5 (see Figure 4). In a partial evaporative type heat exchanger 10, the metal sheet 4 of every radiating fin 1 is partially covered by the respective water absorptive covering 5 and partially exposed to the air (see Figure 5).

Referring to Figures 6 and 7 and Figure I again, when a high performance full evaporative type heat exchanger 9 is installed in an air conditioning system or refrigerator, cooling water is supplied to the water absorptive coverings 5 of the radiating fins I by force or by means of potential difference, and fan means is turned by a fan motor to cause currents of air, enabling water to be quickly evaporated from the radiating fins 1.

Referring to Figures 8 and 9 and Figure I again, when a high performance partial evaporative type heat exchanger 10 is installed in for example a window mounting air conditioning system, condensed water from the condenser 8 is guided to the radiating fins 1 of the heat exchanger 10 to make a heat exchange process. According to test, when one gram of cooling water is evaporated from the radiating fins 1, about 539 calories of heat is carried away from the heat exchanger.

It is to be understood that the drawings are designed for purposes of illustration only, and are not intended as a definition of the limits and scope of the invention disclosed.

1 6 What the invention claimed is; 1. A high performance evaporative heat exchanger comprising:

a front end plate and a rear end plate connected in parallel-, a plurality of radiating fins connected in parallel between said front end plate and said rear end plate, said radiating fins each comprising a metal sheet and a water absorptive covering covered on said metal sheet; and a plurality of heat conductive tubes mounted in holes on said radiating fins and connected between said-front end plate and said rear end plate; wherein cooling water is supplied to the water absorptive coverings of said radiating fins to absorb heat from said heat conductive tubes, and to carry heat away from said radiating fins when evaporated.

2. The high performance evaporative heat excha nger of claim I where the water absorptive covering of each of said radiating fins is covered on the whole surface of the respective metal sheet.

3. The high performance evaporative heat exchanger of claim I wherein the water absorptive covering of each of said radiating fins is covered on a part of the respective metal sheet.

I - 7 4. The high performance evaporative heat exchanger of claim I wherein said. heat conductive tubes are flat tubes each having two opposite ends respectively terminating in a respective circular orifice.

5. High performance evaparative heat exchangers as claimed in claim I and as herein described.

6. High performance evaparative heat exchangers as as herein described and illustrated in the accompanying drawings.

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