JPS589107Y2 - heat exchange equipment - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a heat exchange device equipped with a finned heat exchanger used in air conditioning equipment, refrigeration equipment, etc.

A conventional heat exchange device will be described with reference to FIG. 1. 1 is a finned heat exchanger, 2 is a plurality of heat exchanger tubes, and 3 is a fin, which is attached to the outer peripheral wall of the heat exchanger tube 2.

4 is a tact, and 5 is a blower. Arrow A indicates the direction of air flow as a heat medium by the blower 5.

In the conventional device, heat exchange was performed between the primary heat medium passing through the heat transfer tube 2 configured as described above and the air serving as the secondary heat medium passing between the fins 3.

Generally, the heat transfer coefficient between the air flowing over the fin surface and the fin 3 increases in proportion to the degree of turbulence in the air flow.

In addition, the heat transfer coefficient between the air and the fin surface is very small compared to the heat transfer coefficient between the heat medium flowing in the heat exchanger tube 2 and the inner wall of the tube, so improving the heat transfer coefficient on the air side is by heat exchange. A very large effect can be obtained in improving the efficiency of the device.

In the conventional device, the air flow blown between the fins 3 by the blower 5 has a substantially constant wind speed, and the strength of the turbulence of the air flow is also determined by this wind speed and the structure of the finned heat exchanger.

When such a steady air flow flows along the fin surface, a thick boundary layer of air develops on the fin surface that prevents an increase in heat transfer coefficient.

Therefore, the heat transfer coefficient between the air flow and the fin surface cannot be increased beyond a value determined by the steady state.

Furthermore, as the turbulence of the airflow increases, the boundary layer becomes thinner, but this turbulence does not leave the steady state of turbulence.

This idea was made in view of these conventional drawbacks, and it forcibly creates turbulence in the airflow that flows steadily along the fin surface, preventing the development of a boundary layer and improving the heat exchanger. The aim is to improve the efficiency of

One embodiment of this invention will be explained with reference to Figs. 2 to 4. In Fig. 2, the same reference numerals as in Fig. 1 indicate corresponding parts;
6 is a fixed screen for forming turbulence provided between the heat exchanger 1 and the blower 5; 1 is a movable screen for forming turbulence; and 8 is a drive device for moving the movable screen 7.

FIG. 3 is an enlarged view of a part of the fixed screen 6 and the movable screen 7, in which 10 is a through hole in the screen 6;
Reference numeral 1 designates a closing portion, 12 a through hole in the movable screen 7, 13 a closing portion, and 14 a support arm for moving the movable screen IJ-phone.

The areas of the through holes 10, 12 and the closed portions 11.13 are formed to be approximately equal.

When the support arm 14 of the movable screen 7 is periodically raised and lowered by the drive device 8, the through holes 10, 12 and the closed portions 11, 13
overlap alternately.

This opens and closes the air passage periodically.

In the heat exchange device configured as described above, air is constantly blown through the front groove of the screen 6.7 by the blower 5, but since the through holes 10 and 12 of the screen are periodically opened and closed, the heat exchanger 1 As shown in Figure 4, the wind speed flowing into the area fluctuates intermittently.

This variation in wind speed prevents the growth of a boundary layer of air along the surface of the fins 3, thereby improving the efficiency of the finned heat exchanger 1.

Further, when the air passage is blocked by the screen 6.7, it is not necessary to make it completely airtight, and it is sufficient to simply have a function of reducing the wind speed to approximately 0, so it can be manufactured at low cost.

Figure 5 shows another embodiment of this invention, with screen 6.10
FIG.

In this example, in the center of the air passage, the blockage parts 11 and 13 and the through hole 10
, 12 are formed so that the left and right sides are reversed.

Therefore, when the movable screen 7 moves up and down, the left and right through holes 10 and 12 alternately open and close with respect to the center of the air passage, so that the entire air passage does not close. The wind speed flowing into 1 fluctuates alternately from left to right, which prevents the development of a boundary layer.

In addition, since the entire air passage is not closed, it has the feature that wind pressure loss in the air passage can be reduced.

As described above, according to this invention, the flow of the heat medium passing through the finned heat exchanger is disturbed by changing the air path of the finned heat exchanger, so that the heat medium and the fin surface are The heat transfer coefficient of the heat exchanger can be increased, thereby providing an efficient heat exchange device.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional heat exchange device, Fig. 2 is a cross-sectional view of an embodiment of this invention, Fig. 3 is a cutaway perspective view showing an enlarged main part of Fig. 2, and Fig. 4 shows the main part. FIG. 5 is a characteristic diagram showing the fluctuation state of wind speed, and a cutaway perspective view showing the main part of another embodiment of this invention. In addition, the same reference numerals in the figures indicate the same or equivalent parts, 1 is a heat exchanger with fins, 2 is a heat exchanger tube, 3 is a fin, 5 is a blower, 6 is a fixed screen, 7 is a movable screen, 10,
12 is a through hole.

Claims (3)

[Scope of utility model registration request] (1) In a heat exchange device equipped with a finned heat exchanger in which a plurality of fins are attached to the outer circumferential wall of a heat transfer tube, a plurality of turbulent flow forming screens having a plurality of through holes are used as a heat transfer medium of the fins. A heat exchange device provided on the inflow side and configured to disturb the flow of the heat medium to the fins by driving these screens so that the positions of their through holes mutually vary. (2) Utility model registration Claims In the heat exchange device according to claim 1, the screen is installed parallel to the front surface of the heat exchanger, and the screen is composed of a fixed screen and a movable screen, and the movable screen A heat exchange device that drives only the (3) Utility Model Registration The heat exchange device according to claim 1, wherein the positions of the through holes of the plurality of screens are aligned alternately on the left and right sides by the above-mentioned driving.