KR20030081612A - Plastics heat exchanger for exhaust heat withdrawal - Google Patents

Abstract

PURPOSE: A plastic heat exchanger for recovering exhaust heat is provided to reduce cost, and to prevent deterioration of heat exchange performance. CONSTITUTION: A plurality of heat transfer plates(10) forming a heat exchanger are square to be easily laminated, and having pairs of corresponding sides opened to allow exhaust air or outside air to pass in one direction. A pair of circumference parts of the heat transfer plate facing each other are formed to be concave sides(11) concave more than the other circumference parts neighboring. The other pair of the circumference parts are protrusively formed to be joining sides(12). The concave sides allow exhaust air or outside air to pass. An upper side and a lower side corresponding with the concave sides and the joining sides form joining sides and concave sides naturally protruding and caving in. A heat transfer side(13) is formed on a center of the heat transfer plate. The heat transfer side is formed to be wavy and jagged in diagonal direction between the concave side and the joining side to maximize heat transfer area per unit plate so as to improve heat transfer rate and to allow turbulence to be easily generated.

Description

Plastic heat exchanger for exhaust heat withdrawal}

The present invention relates to a heat exchanger that can save the heating and cooling energy by recovering the exhaust heat discharged from the air conditioning device of industrial and commercial buildings or the ventilation device of the apartment, underground shopping mall, subway, etc., in particular, the heat transfer plate is formed of a thin plastic film It relates to a plastic heat exchanger for exhaust heat recovery that the heat transfer surface in which the heat transfer takes place is formed in a wavy shape so that the heat exchange area can be widened and convective heat transfer can be promoted.

In recent years, the use of air conditioning and ventilation systems for heating and cooling has been expanded due to the pursuit of a pleasant environment, which has led to a surge in energy consumption in summer and winter.

In particular, since the exhaust heat from the air conditioning system and the ventilation device is low in temperature, the amount of exhaust heat is very high, and since the exhaust heat can be directly used for heating or cooling the introduced outside air, it is urgent to take measures against exhaust heat recovery.

In addition, as part of energy saving, indoor spaces are required to be more sealed and insulated, and as a result, the amount of indoor air deteriorates as the amount of ventilation is reduced. To solve this problem, it is required to install a ventilation system equipped with an appropriate exhaust heat recovery system. When the exhaust heat recovery device is used, 50 to 70% of the exhaust heat can be recovered to save a considerable amount of energy for heating and cooling.

In the conventional air conditioning system, a rotary heat storage heat exchanger, a heat pipe type heat exchanger, and an aluminum plate heat exchanger are mainly used for exhaust heat recovery.However, these heat exchangers are difficult to maintain and manage and are expensive, so they are avoided by architects or building owners. Applicable only to some commercial buildings. Therefore, it is being replaced by a small heat exchanger that is inexpensive, easy to install, and has excellent heat transfer performance.

Until now, aluminum has been mainly used as a material of the heat exchanger for exhaust heat recovery, but there have been many difficulties in manufacturing a heat exchanger by stacking a plurality of heat transfer plates manufactured using the aluminum. In other words, in the past, when a plurality of heat transfer plates are stacked and the heat transfer plates are bonded to each other, the process of the heat transfer is very complicated and additional manpower is required by bending the edges of the two heat transfer plates and folding the edges of the other heat transfer plates. The productivity was lowered.

As a result, the use of various non-metallic materials such as plastic or paper is increasing. Non-metal heat exchangers have the advantages of low cost, light weight, and low risk of corrosion. However, since the thermal conductivity is very low compared to aluminum, there was a problem that the heat transfer performance is reduced.

In other words, conventional plastic heat exchangers using non-metallic materials have not been studied yet, and most of them have not been studied to promote heat transfer. Therefore, the conventional plastic heat exchanger has a simple flat plate-like shape, and shows low heat exchange efficiency. The energy saving effect was weak compared to the aluminum heat exchanger.

The present invention provides a heat transfer plate made of a thin film of plastic as a way to eliminate the above problems, by forming the heat transfer surface into a wavy concave-convex to increase the heat exchange area and to promote convective heat transfer to the existing aluminum heat exchanger While the price is much lower than that, it is possible to simultaneously solve the problem of deterioration of thermal performance, which is a problem of the plate-type plastic heat exchanger used in the related art.

In addition, by forming the concave-convex surface alternately in the four corners of the heat transfer plate to the heat transfer plate to be manufactured by a simple process of heat-sealing the convex portion and the convex portion that is in close contact with each other after loading the heat transfer plate alternately in the 90 ° direction.

The present invention has the effect of increasing the heat transfer area by increasing the heat transfer area per unit plate by forming a thin plastic heat transfer plate of the wave shape, the flow path is formed by complexly bonding the wavy irregularities of the heat transfer plate in the 90 ° direction alternately This makes it easy to generate turbulence even at low speeds, which can dramatically improve heat transfer performance and provide a heat exchanger by a simple manufacturing process.

1 is a perspective view of a wavy heat exchanger to which the present invention is applied

2 is an exploded perspective view of the present invention wavy heat exchanger

3 is a plan view schematically showing an exhaust heat recovery state of the present invention;

4 is a cross-sectional view taken along the line A-A of FIG.

5 is a cross-sectional view taken along the line B-B of FIG.

6 is a performance evaluation of the present invention

7 is a plan view of another embodiment of the present invention;

[Explanation of symbols on the main parts of the drawings]

1: heat exchanger 10: heating plate 11: recessed surface

12: joint surface 13: heat transfer surface

The configuration of the present invention is clearly shown by Figs. 1 to 3, the detailed description of the possible degree based on this is as follows.

The plurality of heat transfer plates 10 constituting the heat exchanger 1 of the present invention may be easily stacked in a rectangular shape, and the exhaust heat or external air may pass in either direction after the stacking is completed. The pair of side portions take an open form.

To this end, any one pair of edges facing the heat transfer plate 10 is formed as the recessed surface 11 to be recessed than other adjacent edges, and the other pair of edges adjacent to the recessed surface 11 protrudes from the joint surface ( 12) form.

That is, the four corners of the heat transfer plate 10 are formed with irregularities, through which the discharge air or external air may pass through the recessed surface 11, and the upper and lower surfaces corresponding to the recessed surface 11 and the joint surface 12. Naturally forms a protruding and recessed joining surface 12 and recessed surface 11.

In the central portion of the heat transfer plate 10 is formed a heat transfer surface 13 which is the core technology of the present invention. The heat transfer surface 13 is formed in the shape of a wave-shaped unevenness in the diagonal direction between the recessed surface 11 and the joint surface 12 to maximize the heat transfer area per unit plate to improve the heat transfer amount and at the same time easily generate turbulence To help.

Meanwhile, the heat transfer plate 10 is made of plastic such as polypropylene (PP) as a main raw material, but the heat transfer coefficient 13 is combined with heat transfer acceleration technology in order to prevent heat transfer performance from lowering in the heat transfer coefficient compared to conventional aluminum. By reducing the convective heat resistance between the heat transfer performance can be improved over the existing aluminum heat exchanger.

In the present invention, unlike the conventional complicated work process in forming a heat exchanger 1 by stacking a plurality of heat transfer plates 10 having such a configuration, in the present invention, the wave shapes of the heat transfer surfaces 13 are alternately 90 as shown in FIG. 2. The heat exchanger can be manufactured by a simple process of laminating the heat exchanger of the heat transfer plate 10 of the heat transfer plate 10 and the joining surface 12 of the other heat transfer plate 10 corresponding to the heat transfer plate 10. Will be.

Therefore, the heat transfer plate 10 is in a state in which the junction surface 12 is sealed and the inlet surface 11 is open, so as shown in FIG. 4, an inlet 14 and an outlet 15 through which air can be naturally introduced and discharged. It forms a and through the inlet 14 and the outlet 15 it is possible to flow the discharge air or external air only in one direction.

In addition, as the heat transfer plate 10 is alternately stacked in the 90 ° direction, the inlet port 14 and the outlet port 15 are installed in a cross flow state, so that only the exhaust air is allowed to pass through the pair of concave inlet surfaces 11 and adjacent to each other. Through the other concave inlet surface 11 through the outside air alone to allow the heat exchange between the exhaust air and the inlet air in the cross-flow state between the heat transfer plate (10).

Here, the discharge air and the external air passing between the heat transfer plates 10 pass through a flow path formed more complicated by the wavy heat transfer surface 13, so that the time (heat exchange time) staying between the heat transfer plates 10 is As it flows along the elongated and wavy curves, it easily generates turbulence even at low speeds, which dramatically improves heat transfer performance.

Figure 6 shows the results of performing the performance evaluation by designing, manufacturing a conventional flat-pin type, the wave shape of the present invention using a plastic for the performance evaluation of the present invention.

According to the results of the performance evaluation, the heat transfer performance and the pressure loss at the same time considering the performance of the same blower power as a result of the present invention at a surface wind speed of 2.5m / sec, the heat transfer performance is 41 compared to the flat type without heat transfer promotion technology It is increased by%, 72% compared to the flat plate-type used in the prior art, it can be seen that the performance is further improved as the wind speed increases.

On the other hand, the overall shape of the heat transfer plate 10 in the present invention is carried out in various forms, including, but not limited to the rhombus or hexagonal shape, even if the overall shape change of the heat transfer plate 10 to the scope of the present invention Cannot escape.

In addition, Figure 7 shows a plan view of another embodiment of the present invention as a secondary shape of the wavy irregularities in the longitudinal direction of the irregularities on the heat-transfer surface 13 made of wavy irregularities, it is possible to further improve the heat transfer performance .

The present invention can recover 50% to 70% of the exhaust heat of the air conditioning and ventilation of the vast amount of apartments, commercial buildings, underground malls, subways, factories, etc., which are largely discarded, and thus it is possible to save energy drastically. While the price is much lower than that of the heat exchanger, it is possible to improve the thermal performance by more than 50% compared to conventional flat-pin plastic heat exchangers.

In addition, since plastic is used as a main raw material, it is possible to prevent environmental pollution through recycling.

Claims (3)

The concave indentation surface 11 is formed such that any pair of edge portions of the thin plastic heat transfer plate 10 facing each other is recessed, The other pair of opposing edge portions adjacent to the concave inlet surface 11 forms a joining surface 12 to protrude, While the heat transfer surface 13 is formed of wavy convex-concave in order to increase the heat transfer area in a diagonal direction between the recessed surface 11 and the joint surface 12 and to generate turbulence, The heat transfer plate 10 is alternately loaded in a 90 ° direction, but one of the heat transfer plate 10, the concave surface 11 and the joint surface 12 of the other heat transfer plate 10 corresponding to the heat-sealed integrally Plastic heat exchanger for exhaust heat recovery. The method according to claim 1, The discharge air passes through the pair of concave indents 11 facing each other, and the external air passes through the pair of adjacent indents 11 adjacent to each other to allow the exhaust air to pass through the heat transfer plate 10. The heat exchanger and the exhaust air and the outside air flows along the wavy curve of the heat transfer surface 13 to generate turbulence to improve heat transfer performance, characterized in that the plastic heat exchanger for heat recovery. The method according to claim 1, Heat transfer surface 13 is a plastic heat exchanger for exhaust heat recovery, characterized in that the secondary convexly formed wavy irregularities in the longitudinal direction unevenness.