JPS62186195A - Heat exchanger - Google Patents

Abstract

PURPOSE:To reduce static pressure loss while keeping heat exchanging efficiency as it is by a method wherein the ratio of the mutual interval of fins for a flow path defining element to the height of the fin is set within a specified range. CONSTITUTION:In case a plate 2, made of resin and having the thickness of 0.1mm, a fin 3, made of resin and having the height H of 2.9mm, one series of connecting plate 5, made of resin and having the thickness of 0.1mm, are used in the flow path defining element 4 of ladder type and the ratio P/H of the pitch P of the fins to the height H of the fin is changed from 1.0 to 20.0 under the air processing amount of 1,000m<3>/h, heat exchanging efficiency eta1 is reduced suddenly when the P/H is changed from 1.0 into 2.0, however, it is not changed substantially when the ratio P/H is changed from 3.0 to 20.0. On the other hand, a static pressure loss DELTAP is reduced when the P/H is increased, however, the reduction of the pressure loss becomes slow when the P/H is 10.0 or higher. When the P/H is set within the range of 3.0 to 10.0, the static pressure loss in the air flow path between fins may be reduced while the overall size of the profile and the heat exchanging efficiency of the exchanger may be maintained as it is.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a plate-fin type heat exchanger having a vertically laminated structure, and particularly to a plate-fin type heat exchanger that maintains the overall external dimensions and heat exchange efficiency. , which aims to reduce static pressure loss in the air flow path between the fins.

[Conventional technology]

Plate-fin type heat exchangers have a large heat transfer area per unit volume, and are widely used as relatively small and highly efficient heat exchangers.
Heat exchangers are used in counter-current and counter-current types due to the difference in the flow of the two fluids.

It can be divided into three types: orthogonal (oblique) prototypes.

The air-to-air heat exchangers used in air conditioners are usually of the counter-flow type or cross-flow type, but until now the basic configuration of the fist (Yu, as shown in Figure 8) has been used. A plate that partitions two fluids in a heat exchanger (10 is a corrugated plate-shaped fin (102) that configures multiple rows of parallel flow channels.
It is made of layers sandwiched together.

The play in the air conditioner shown in Figure 8) (101)
As shown in FIG. 9, the fins (102) are made of paper material based on Japanese paper that has both heat conductivity and moisture permeability.
(101) is obtained by processing the same paper material into a corrugated plate, but the corrugated plate-shaped fin (10
There was a problem in that the production of 2) involved a lot of labor, resulting in poor productivity.

Another four-component unit heat exchange member (4a) is a unit heat exchange member (4a) that is integrally constructed by sandwiching a flat plate-shaped fin (3) between two upright plate-shaped plates (2) as shown in Fig. 10. A unit heat exchange member (4b) formed by integrally molding a flat plate fin (31) on one side of a flat plate (2) as shown in Fig. 11 is laminated vertically. In all cases, the ratio of the height H of the fins (3) to the distance P between the fins was within the range of 1.0 to 2.5.

This is to increase the area of the fins in order to make the completed heat exchanger compact, and to stabilize the rising angle of the fins against the load from above in the case of the corrugated fins shown in Figure 9. In the case of the fins shown in FIGS. 10 and 11, this was also done to prevent each fin from falling down when stacked.

[Problem that the invention seeks to solve]

In conventional heat exchangers, as mentioned above, in order to make the whole compact, the fins in particular have a large area, so the static pressure loss in the air flow path between the pot fins is
As a result, there was a problem that it became thick.

This invention was made to eliminate the above-mentioned conventional problems, and by researching the optimization of the shape of the flow path between the fins in a heat exchanger, the overall external dimensions and heat exchange efficiency were maintained. The purpose is to reduce static pressure loss compared to conventional ones while maintaining the same level of pressure loss.

[Means for solving problems]

In the case of this invention, the distance P between the fins in the channel defining element formed from the parallel fins and the connecting plates provided at both ends of each fin is P with respect to the height H of the fins.
The flow path defining element (4
) are stacked vertically with plates (2) in between to form a heat exchanger (1).

[For production]

In the case of this invention, the distance P between the fins is 2KH in height.
Since the P/H is set within the range of 3.0 to 10.0, the static pressure loss in the air flow path between the fins is small (and the overall external dimensions and heat Exchange efficiency can be maintained as is.

〔Example〕

An embodiment of this invention will be described below. That is, FIG. 1 is a basic model for testing the heat exchanger of the present invention, and in this model, the height H of the fins in each flow path defining element (4) and the distance P8 between the fins were varied. We conducted an experiment.

FIG. 2 shows the integrally molded ladder-shaped channel-defining element (4) in this case, and each plate (21 The thickness of the plate is 0.
1mm, 2.9ml of Finno High EH! L, the thickness of the series of connecting plates (5) is 0.1 mm, the material of the plates, fins and connecting plates is resin, the amount of air to be processed is 1000, . 3
FIG. 3 shows the experimental results when the distance P between the fins was varied as /h.

As is clear from this figure 3, P/H is 1.0 to 20.
．． When the heat exchange efficiency ηt is changed to 0, P/H is 1.
．． When P/H goes from 0 to 2.0, it decreases rapidly, but when P/H is 3.
There is almost no change from 0 to 20.0. On the other hand, static pressure loss △P decreases as P/H increases, but P/H
When P/H is 4.0 or more, the decrease becomes gradual, and when P/H is 10.0 or more, the decrease is small.

Based on these conditions, the height H of the fins and the mutual fin width should be adjusted so that the heat exchange efficiency ηt at the time of 1000 m'/h processing exhaustion is 6996 in the heat exchanger having the dimensions shown in Fig. 1. The changes in heat exchange efficiency ηt and static pressure loss ΔP with respect to the amount of air to be processed were determined when the interval P was changed, and these are shown in FIG.

As is clear from this figure, the heat exchange efficiency ηt is 1000
If the efficiency at m”/h is 77j = 69%, a o
o,, 7296 in 57 hours. 75 in 600 m'/h
%.

8096 at 400 ms/h.86 at 200 m'/h
It shows exactly the same characteristics as %. On the other hand, static pressure loss is P/H
It can be seen that P/H decreases sharply up to 3.0, but then decreases slightly until P/H reaches 20.0.

In contrast, Fig. 5 shows a conventional heat exchanger employing the corrugated plate-like fins shown in Fig. 8, which has the external dimensions shown in Fig. 1.
The efficiency ηt at a processing air volume of 1000 m5/h is 6
It shows the static pressure loss when P/H=2.0 when it is 9%. As is clear from the comparison between Figures 4 and 5, the conventional heat exchanger using corrugated plate fins has a lower static pressure loss when 13/H is smaller than the heat exchanger of the present invention. Although it has low characteristics, in the case of this corrugated plate-like fin, structurally it is only possible to manufacture a P/H of about 1.0 to 2.5, so reducing static pressure loss is a practical problem. It is impossible.

By the way, in order to achieve a lower static pressure loss than a heat exchanger with corrugated plate-like fins when P/H is 2.0, P/H must be 3.
．． It is sufficient to use the flow path defining element shown in FIG. 2 with a P/H of 0 or more, and it is possible to reduce the loss when the P/H is 10.0 in this case.

Also, compared to the unit heat exchange member having the shape of FIG. 10 or 11 with P/H=1.0 to 2.5, the static pressure loss l is P/H=3.0 and P/H= 58 for 1.0
%, in the case of P/H = 10.0, it is reduced to 65.65 in the case of P/H = 2.5.

Furthermore, as is clear from Figure 3, when P/H is 3.0 or more, there is no decrease in heat exchange efficiency, so it is necessary to increase the number of stacked flow path defining cables to obtain the same heat exchange efficiency. By making the distance P between the fins as thick as possible, the number of required fins is reduced to n.
It becomes possible to manufacture a heat exchanger at low cost.

From the above, it seems that the wider the spacing between the fins, the better, but when actually configured and used as a heat exchanger, the material of the plate (resin 9 paper, thin metal plate)
If the plate thickness ECQ, Q5 is too large, plate deformation is likely to occur due to the pressure between the windows between the plates, and the maximum P/H is 20.0 or less, especially when the material is resin or paper. The P/H is preferably about 10.0.

The example above has been described in which the ladder-shaped flow path defining element (4) is configured to have the same size as the plate 2), but as shown in FIG. Plate (2)
Plate 12+
The heat exchanger may be configured as a counterflow type heat exchanger as shown in FIG.

〔Effect of the invention〕

In the heat exchanger of the present invention, the distance P between the fins of each channel-defining rope constructed in the form of a ladder is set to P with respect to the height H of the fins.
/H = 3.0 to 100, so the static pressure loss is reduced by 10% to 6096 compared to the conventional heat exchanger with P/H = 1.0 to 2.5. In addition, the material used for the fins can be reduced for the same heat exchange efficiency, making it possible to provide a low-cost product.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing a heat exchanger of the present invention, Fig. 2 is a perspective view showing a ladder-shaped flow path defining element of the invention, and Fig. 3 is a perspective view showing a case where the height H of the fins is constant. P/H and heat exchange efficiency η
Fig. 4 shows the change in static pressure loss due to change in P/H when the heat exchange efficiency is the same. Fig. 5 shows the same external shape as the first factor. Figure 6 shows the static pressure loss of a heat exchanger employing corrugated plate-like fins with the same heat exchange efficiency as Figure 4 in dimensions; FIG. 7 is a perspective view showing the main parts of a counterflow type heat exchanger formed by laminating the ones in FIG. 6, and FIG. 8 is a perspective view showing a conventional example. Figures 9, 10, and 11 are side views without showing conventional unit heat exchange members. In the figures, (1) is a heat exchanger, and (2) is a plate 1-.1.
31 is a fin, (4) is a channel defining element, and (5) is a connecting plate.

Claims (3)

[Claims] (1) A ladder-shaped flow path defining element consisting of a plurality of fins arranged in parallel at a predetermined interval and a connecting plate provided at both ends of each fin to bridge the fins. The two plates are stacked vertically with one of the plates in common, and the two air streams to be heat exchanged are passed between each plate alternately, layer by layer. In the case where heat exchange is performed, P/H is within the range of 3.0 to 10.0, where H is the height of the fins of the flow path defining element and P is the interval between the fins. A heat exchanger characterized by: (2) The heat exchanger according to claim 1, wherein the plate is made of a material having heat conductivity and moisture permeability. (3) The heat exchanger according to claim 1, wherein the flow path defining element is integrally molded from resin into a ladder shape.