JPH0665958B2 - Heat exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention holds a flow path defining element, which is formed in a double cross shape by integrally forming side-by-side fins and connecting plates at both ends thereof, between plates. The present invention relates to a plate fin type heat exchanger in which these are stacked in the vertical direction, and more particularly to measures for preventing the fins from collapsing in the flow path defining element.

[Conventional technology]

The plate fin type heat exchanger has a large heat transfer area per unit volume and is widely used as a relatively small and highly efficient heat exchanger. Type, counter flow type, and orthogonal (oblique) flow type. The air-to-air heat exchangers used in air conditioners are usually of the counterflow type or the crossflow type, but until now the basic configuration should be heat exchange as shown in Fig. 12. A corrugated plate-like fin (102) forming a plurality of rows of parallel flow paths is sandwiched between plates (101) for partitioning two fluids. In the air conditioner shown in FIG. 12, the plate (101) is formed of a paper material based on Japanese paper having both heat conductivity and moisture permeability, and the fin (102) is the same as the plate (101). It is obtained by processing a corrugated board from different paper materials. However, as described above, the heat exchanger having the laminated structure in which the fins (102) having the corrugated plate shape are sandwiched between the flat plate (101) has to have two members alternately laminated, so that the productivity is poor. In addition, in the direction of the fin (102) during stacking,
There were some problems when it was easy to make variations. Therefore, as shown in FIG. 13, it has a double girder shape consisting of a plurality of fins (3) juxtaposed at predetermined intervals and connecting plates (5) provided at both ends of each fin and bridging the fins with each other. It has come to be used that a flow path defining element (4a) is sandwiched between plates (2) and these are vertically stacked.

Further, the shape of each fin (3) of each flow path defining element (4a) has a lower bottom width dimension (thickness) with respect to the fin height H as shown in FIG. 14 for the purpose of reducing fin material. ) T to T
Usually, it is constructed within the range of /H=0.01 to 0.3.

[Problems to be solved by the invention]

T of each fin (3) in the conventional flow path defining element (4a)
Since / H is configured in the above ratio, when the flow path defining element (4a) is piled up, for example, as shown in FIG. 1, both end connecting plates (5) as shown in FIG. 15 or 16 are included. In addition, the fins (3) are likely to fall down, which may cause damage to the connecting plate (5), or may cause performance deterioration such as air leakage due to uneven height of the unit heat exchange elements. .

An object of the present invention is to prevent the fins of the flow path defining element from collapsing and to prevent the fins from varying in order to solve the above-mentioned conventional drawbacks.

[Means for solving problems]

In the case of the present invention, the height of each fin of the flow path defining element to be used and the portion to be connected to the plate at the bottom are specified, and in the case of the bottom bottom width dimension T of each fin and the fin height dimension H, T / H is set in the range of 0.5 to 1.5 so that the stability of each fin in the flow path defining element at the time of stacking is further enhanced by the action of the connecting plate and the fin is prevented from collapsing. .

[Action]

In the case of the present invention, the amount of the material used is reduced by specifying the cross-sectional shape of each fin in the flow path defining element, and the fin itself is prevented from collapsing due to the increase in T / H. A reaction force is generated, and the synergistic action with the connecting plates at both ends provides an effective fall prevention action.

〔Example〕

First, considering the direction of force and the tilting direction when the conventional fin (3) having the shape shown in FIG. 17 is obliquely contacted by the load from the upper part, the fin (3) is tilted as shown in the figure. , When the flow path defining element of the upper stage is placed on the plate via the plate (2) and a load is applied, a downward force F is applied to the upper part of the fin (3), and a reaction force F ₁ against it is decreased. Because of the two forces F and F ₁ generated at the bottom, the rotational force A
Occurs in the direction shown, which causes the fin (3) to fall. From this, in the case of the present invention, the fins (3) of the flow path defining element (4) are formed as shown in FIGS. 2 and 3. In this case, as shown in FIG. / H
Therefore, if this fin is tilted at the same angle as in the case of FIG. 17, and another similar flow path defining element is placed on it through the plate (2) and a load is applied, Since the force F and the reaction force F ₁ applied to (3) are in the state shown in FIG. 3, the rotational force A is applied in the direction to prevent the fin itself from collapsing as shown in the drawing, and the fin ( The fall of 3) is effectively prevented by the synergistic action with the connecting plates (5) provided at both ends. Specifically, T / H should be 0.47 or more when the allowable tilt angle of each fin is 25 °, and T / H when the allowable tilt angle is 60 °.
Is 1.732, and it has been experimentally confirmed that the optimum T / H is 0.5 to 1.5 in the case of a general flow path defining element material currently used.

Further, FIGS. 4, 5 and 6 show an embodiment of the flow path defining element of the present invention in consideration of reduction of the amount of material in the fin portion. That is, in order to prevent the fin (3) from collapsing as described above, the T / H should be set to a minimum of about 0.5, but a T / H of about 1 is desirable from the practical viewpoint. However, in the case of this shape, the amount of material used as fins is twice as much as that in the case of T / H = 0.5, and the cost increases accordingly, so to improve this, as shown in FIG. , The amount of material used while securing a wide lower bottom width T as a trapezoid of the upper bottom width W and height H that connect to the above plate at the bottom of the fin and the upper bottom. Is to decrease, and in this case T / H = 1.0 and W / T = 0.2, the cross-sectional area of fin (3) is Therefore, this is the same as in the case of a rectangular cross section with T / H = 0.6. Then, when the amount of change in the height of the bottom surface for obtaining the same inclination is calculated, the trapezoid with T / H = 1.0 is 1.67 times that of the rectangle with T / H = 0.6, which is 1 / The stability of the fin itself is increased because only the inclination of 1.67 occurs. That is, the trapezoidal cross-section makes it possible to save the material used as fins while ensuring the stability of the fins. At this time, if the W / T ratio is 0.4 or less, the effect of material reduction is high, but it is desirable to use it in the range of 0.1 to 0.9 in consideration of the molding method of this shape.

Also, FIGS. 7, 8 and 9 are examples for further reducing the amount of material used as compared with the above trapezoidal fins, and the W / T in these cases is set in the range of 0.1 to 0.9. It Further, the plate for partitioning the fluid can exchange sensible heat if it has heat conductivity, but if it is made of a material having heat conductivity and moisture permeability, both sensible heat and latent heat, that is, total heat Exchange is possible, and heat recovery efficiency as an air-to-air heat exchanger can be increased.

Others Fig. 10 has a pair of upper and lower flow passage inlets (6) on the front side for alternately passing two air streams to be heat-exchanged,
In addition, it is a case where the flow path defining element having the fin configuration shown in FIGS. 2 to 9 is implemented in the counterflow heat exchanger opened so that the outlet (7) faces in the opposite direction to the left and right. Fig. 11 shows that the outermost fin (3) is formed wider than the other fins (3) in the middle to improve the assemblability when forming the heat exchanger and prevent air leakage after completion more reliably. The fin configuration shown in FIGS. 2 to 9 is adopted at the same time.

〔The invention's effect〕

As is apparent from the above-described embodiments, the present invention sandwiches a double-sided flow path defining element between flat plates as a heat exchanger, and uses one of the plates in common in the vertical direction. Since the height of the fins of the flow path defining element and the part that connects to the plate at the bottom are specified as described above, it is more effective due to the synergistic action with the connecting plates at both ends of the fin. In addition, the fins can be prevented from collapsing to prevent the fins from varying and the heat transfer efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a cross-flow heat exchanger as an application example of the present invention, and FIG. 2 is a side view showing a dimensional relationship of fins in a flow path defining element showing an embodiment of the present invention. Fig. 3 is a side view showing the force relationship when the fall of the fin is corrected,
4, FIG. 7, FIG. 8 and FIG. 9 are side views showing various flow path defining elements which are other embodiments of the present invention, and FIG. 5 is a dimensional relationship of fins in FIG. Side view,
FIG. 6 is a side view showing the force relationship when the fin collapse is corrected, and FIG. 10 is a counterflow type heat composed of a laminated body of a flow path defining element and a plate in which the fin structure of the present invention is implemented. FIG. 11 is a perspective view of the exchanger, and FIG. 11 is a perspective view showing a flow path defining element for a cross-flow heat exchanger in which the fin structure of the present invention in which the outermost fin is formed wider than other fins in the middle is implemented. Figure,
FIG. 12 is a perspective view of a conventional cross-flow heat exchanger using corrugated plate fins, and FIG. 13 is a conventional cross-shaped flow path defining element in which fins and connecting plates between them are integrally molded. Figure 14 is a side view showing the dimensional relationship of the fins, Figure 14
FIG. 16 and FIG. 16 are side views showing the collapse of the fin when the flow path defining element is used, and FIG. 17 is a side view showing the force relationship when the fin is collapsed. In the figure, (1) is a heat exchanger, (2) is a plate,
(3) is a fin, (4) is a flow path defining element, (5) is a connecting plate, (6) is an inlet, (7) is an outlet, T is a bottom width dimension, H is a height dimension, W is The upper bottom width dimension is shown.

Claims (6)

[Claims] 1. A double girder-shaped flow path defining element comprising a plurality of fins arranged in parallel at a predetermined interval and connecting plates provided at both ends of each fin and bridging the fins with each other. It is sandwiched between plates that have
Heat should be exchanged with the flow path divided by each plate 2
In a structure in which two air streams are alternately passed through to perform air-to-air heat exchange, a bottom width dimension T connected to the plate at the bottom of each fin of the flow path defining element
A heat exchanger characterized in that a ratio T / H of the height dimension H and the height dimension H is set within a range of 0.5 to 1.5. 2. W / T, where T is the bottom width of the fin connecting to the plate at the bottom of each fin, and W is the top width connecting at the top of the fin.
The heat exchanger according to claim 1, wherein the trapezoidal shape has a value of 0.1 to 0.9. 3. W / T when the bottom width dimension T connecting to the plate at the bottom surface of the fin and the top bottom width dimension W connecting at the top surface are W / T
Within the range of 0.1 to 0.9 Convex, Alternatively, a combination of these shapes may be used.
The heat exchanger according to the item. 4. The heat exchanger according to any one of claims 1, 2, and 3, wherein the plate is made of a material having heat conductivity and moisture permeability. 5. A pair of upper and lower flow passages in which two flow passages for heat exchange are alternately passed by stacking the flow passage defining elements in a vertical direction through plates, and the inlets thereof are on the same side of the front surface. The heat exchanger according to any one of claims 1 and 2, wherein the heat exchanger is formed in a counter-flow type having an outlet on both sides so as to face left and right opposite directions. 6. An outermost fin of the flow path defining element, wherein a connecting surface with the plate is set wider than the other fins between the fins. The heat exchanger described in any of the above.