JPH0264397A - Fin tube type heat exchanger - Google Patents

Abstract

PURPOSE:To unify the distribution of the speed of air passing between plate fins and improve heat transfer performance by reducing gradually the number of cut-and-raised parts from a position near a cross-flow fan toward another position remote from the same fan. CONSTITUTION:When heat medium such as fluorocarbon or the like is made to flow through heat transfer tubes 2 and a cross-flow fan 7 is rotated, indoor air passes between the plate fins 1 of a fin tube type heat exchanger 6 to effect heat exchange between the heat medium and is made to flow into a room as cold airflow or warm airflow. The number of cut-and-raised parts 4, provided on the fin plate 1, is reduced gradually from a position near the cross-flow fan 7 and the resistance coefficient of air is also reduced gradually whereby the air speed distribution of the flow of air, generated by the rotation of the cross-flow fan 7, becomes uniform regardless of a distance from the cross-flow fan 7. As a result, sufficient air speed may be obtained at a position on the plate fin 1, which is remote from the cross-flow fan 7, whereby heat transfer performance may be improved, the ineffective part of the fin tube type heat exchanger 6 may be reduced and the heat exchanging capacity as the whole of the heat exchanger may be improved.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is a fin-tube heat exchanger that is provided in an air conditioning indoor unit using a cross-flow fan and that takes in heat from indoor air or releases heat to indoor air. It is related to vessels.

BACKGROUND OF THE INVENTION Conventionally, in this type of fin-tube heat exchanger, as shown in FIG. , cut and raised portions 4 were provided in the same pattern on the plate fins 1 between the heat exchanger tubes 2 of each stage.

Further, as shown in FIG. 4, the indoor unit 5 was provided with this fin-tube heat exchanger 6 on the indoor air inflow side, and a cross flow fan 7 was provided on the air outflow side of the indoor unit 5.

That is, by flowing a heat medium such as fluorocarbon into the heat transfer tubes 2 and rotating the cross flow fan 7, indoor air is passed between a large number of plate fins 1 arranged at regular intervals in the fin tube heat exchanger 6. It exchanges heat with a heat medium and blows cold or warm air into the room.

Problem to be Solved by the Invention However, in the configuration of such a fin-tube heat exchanger 6, as shown by the arrow in FIG.
The wind speed passing through the cross-flow fan 7 has a wind speed distribution such that the farther from the cross-flow fan 7, the lower, and the closer it is, the higher the wind speed.
Due to this non-uniform distribution, there was a problem in that the heat transfer performance of the fin-tube heat exchanger 6 was not sufficiently exhibited.

In other words, the cut-and-raised portions 4 of the plate fin 1 are provided in the same pattern everywhere, so the resistance coefficient on the air side is the same regardless of the distance from the cross-flow fan 7. This will result in a wind speed distribution like this. Cross flow fan 7 with plate fin 1
In areas far away from the area, the wind speed is low, causing turbulence in the airflow, and the effect of the cut-and-raised portion 4 provided to improve heat transfer performance is maximized. I couldn't do it.

Therefore, in the present invention, the air side resistance coefficient of the plate fin is
The purpose of this project is to obtain a fin-tube heat exchanger that improves heat transfer performance by uniformizing the distribution of wind speed passing between plate fins by varying the distance from the cross-flow fan.

Means for Solving the Problems In order to achieve the above object, the present invention has a structure in which the number of cut and raised portions provided on the plate fins is gradually reduced in the step direction of the heat exchanger tubes.

Effect The fin-tube heat exchanger of the present invention has the above-mentioned configuration, so that the number of cut and raised parts gradually decreases from a position nearer to a position farther from the crossflow fan, so the air side resistance coefficient also gradually decreases, and the crossflow When the flow fan rotates, the wind speed distribution becomes uniform. As a result, there is sufficient air velocity even between the plate fins located far from the crossflow fan of the fin-tube heat exchanger, and heat transfer performance does not deteriorate.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. In Figures 1 and 2, l is a plate fin,
Reference numeral 2 designates a multi-stage heat transfer tube that vertically passes through the plate fin 1. By expanding the tube, it comes into close contact with the collar 3 provided on the plate fin 1.
A large number of cut and raised portions 4 are provided to disturb the airflow.

The number of cut-and-raised portions 4 is such that the heat source is formed from one end of the plate fin 1 to the other end, that is, from the lower stage of the heat exchanger tube 2 to the upper stage. When the heat exchanger is provided, the number of cut and raised portions 4 gradually decreases from a portion close to the cross flow fan 7.

Next, the operation of the configuration of this embodiment will be explained. When a heat medium such as fluorocarbon is flowed through the heat transfer tube 2 and the cross flow fan 7 is rotated, the indoor air passes between the fins 1 of the fin-tube heat exchanger 6, exchanges heat with the heat medium, and becomes cold air or warm air. It turns into wind and blows into the room. At this time, since the number of cut-and-raised parts 4 provided on the plate fin 1 gradually decreases from the part near the cross-flow fan 7, the resistance coefficient on the air side also decreases, and the rotation of the cross-flow fan 7. As shown by the arrows in FIG. 2, the air flow has a uniform wind speed distribution regardless of the distance from the cross-flow fan 7.

As a result, even in the portion of the plate fin 1 that is far from the cross-flow fan 7, there is sufficient air velocity, the heat transfer performance is improved, and the ineffective portion of the fin-tube heat exchanger 6 is reduced, which improves the overall heat exchange. Your ability will improve.

In addition, by making the wind speed distribution uniform, when producing the same air volume, the amount of work of the crossflow fan is reduced compared to when the wind speed distribution is uneven, and the rotation speed can be reduced.
It also saves power consumption and reduces noise levels.

Effects of the Invention As described above, the present invention has a fin-tube heat exchanger configuration in which the number of cut-and-raised portions of the plate fins is gradually reduced in the direction of the heat transfer tube stages. It is possible to make the wind velocity distribution of the air uniform, the entire heat exchanger can be used effectively, and the heat transfer performance is improved. In addition, by making the air velocity distribution uniform, the air-side pressure loss of the entire fin-tube heat exchanger is relatively reduced, which also reduces the workload of the cross-flow fan, reducing power consumption and noise levels. can also be measured.

[Brief explanation of the drawing]

Fig. 1 is a front view of a plate fin of a fin-tube heat exchanger showing an embodiment of the present invention, and Fig. 2 shows the configuration and wind speed distribution when the fin-tube heat exchanger is installed in an indoor unit. Figure 3 is a front view of the plate fins of a conventional fin-tube heat exchanger, and Figure 4 is a configuration diagram showing the configuration and wind speed distribution when a conventional fin-tube heat exchanger is installed in an indoor unit. be. ■... Plate fin, 2... Heat transfer tube, 3... Collar, 4... Cut-and-raised part, 5... Indoor unit, 6...Fin tube heat exchanger, 7...Cross flow fan. Name of agent Patent attorney Shigetaka Awano 1 person 5 - Indoor unit O - - Finchi - Type 7 Jukubun Nanasara j (7° - Crossf 0-77n Figure 1 / ° -7 # Rate fin 2 - Ira = v, v /-7' rate fin 2 --- Iyon ?, v

Claims (1)

[Claims] The plate fins are provided with a large number of parallel plate fins arranged in parallel at regular intervals, and multi-stage heat transfer tubes passing through these plate fins, and the plate fins are provided with a large number of cut and raised portions that disturb the air flow. A fin-tube heat exchanger in which the number of raised portions is gradually decreased in the direction of the stages of the heat transfer tube.