JPH03211396A - Air conditioner - Google Patents

Abstract

PURPOSE:To uniformize distribution of air flow velocity and contrive an increase in the heat-exchanging efficiency of a finned tube heat exchanger, by a construction wherein the height of cut-and-raised parts of plate fins is decreased with increasing distance from a cross flow fan. CONSTITUTION:When a heat transfer medium such as CFC is passed through a heat exchanger tube 1 and a cross flow fan 7 is rotated, room air flows between plate fins 3a of a finned-tube type heat exchanger 5a, thereby exchang ing heat with the heat transfer medium, before being blown into a room as cold air or hot air. The height of cut-and-raised parts 2a of the plate fins 3a is gradually decreased with increasing distance from the cross flow fan 7. The drag coefficient of air flow is kept also decreased for a while, accordingly. Therefore, the flow of air by rotation of the cross flow fan 7 has a substantially uniform distribution of flow velocity, regardless of distance from the fan 7. Thus, a sufficient air flow velocity is attained even at the plate fins 3 far from the cross flow fan 7, resulting in an enhanced heat transfer performance and an enhanced total heat-exchanging performance.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an air conditioner using a fin-tube heat exchanger and a cross-flow fan.

BACKGROUND OF THE INVENTION In recent years, air conditioners using cross-flow fans and fin-tube heat exchangers having plate fins with a number of cut-out portions that disrupt airflow have become mainstream.

Conventionally, this type of air conditioner has generally had the configuration shown in FIGS. 4 to 6.

As shown in the figure, a plate fin 3 having a large number of cut-out portions 2 disturb the air flow at the same height near the through holes through which the heat exchanger tubes 1 provided in multiple stages pass is installed.
A fin-tube heat exchanger 5 is constructed by passing the heat exchanger tube 1 through the heat exchanger tube 1 through a collar 4 provided in the heat exchanger 1, and arranging a large number of the plate fins 3 in parallel at regular intervals. The fin-tube heat exchanger 5 is provided on the indoor air inflow side of the main body 6 of the air conditioner, and the cross-flow fan 7 is provided near the lower end of the fin-tube heat exchanger 5 on the air outflow side. ing.

In the above configuration, when a heat medium such as fluorocarbon is flowed through the heat transfer tube 1 and the cross flow fan 7 is operated, heat is exchanged when indoor air passes through the fin tube heat exchanger 5.
It becomes cold air or warm air and is radiated into the room from the air outlet side.

Problems to be Solved by the Invention In such a conventional air conditioner, as shown by the arrow in FIG. It has a wind speed distribution in which the closer it is, the higher it is, and when the heights of the cut-out portions 2 formed on the plate fins 3 are the same, the air flow resistance coefficients of the fin-tube heat exchanger 5 are the same. Therefore, this wind speed distribution is not relaxed, and the effect of the cut-out portion 2 provided to improve heat transfer performance by causing turbulence in the air flow is small, and the Heat exchange performance was poor.

The present invention is intended to solve the above-mentioned problems, and aims to provide an air conditioner that improves heat exchange efficiency by uniformizing the wind speed distribution passing through a fin-tube heat exchanger regardless of the distance between the cross-flow fans. purpose.

Means for Solving the Problems In order to achieve the above object, the present invention includes a large number of plate fins arranged in parallel at regular intervals and having a large number of cut-and-raised portions that disturb airflow, and this plate. A fin-tube heat exchanger formed by multi-stage heat transfer tubes passing through fins, and a cross-flow fan that forms an air flow through the fin-tube heat exchanger are installed at one end of the fin-tube heat exchanger. The height of the raised portion of the plate fin is configured to decrease as the distance from the cross flow fan increases.

According to the above-described configuration, the height of the cut-out portions provided on the plate fins decreases from a position close to the cross-flow fan to a position farther from the cross-flow fan. The drag coefficient of the airflow also decreases as it moves away from the crossflow fan, and as a result, the air velocity distribution becomes uniform regardless of the distance from the crossflow fan, increasing the heat exchange efficiency in the fin-tube heat exchanger.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3. In addition, in the present invention, the height of the cut-and-raised portion of the conventional plate fin is reduced as the distance from the cross-flow fan increases, and the same parts as in the conventional one are given the same numbers and the description thereof will be omitted.

As shown in the figure, the cut-and-raised height t of the cut-and-raised portion 2a provided on the plate fin 3a is gradually lowered from the bottom to the top of the plate fin 3a, that is, from the bottom to the top of the heat exchanger tube 1. A fin-tube heat exchanger 5a is formed, and is provided on the indoor air inflow side of the main body 6 of the air conditioner, and a cross flow fan 7 is provided near the lower end of the fin-tube heat exchanger 5a on the air outflow side. ing.

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 1 and the cross flow fan 7 is rotated, the indoor air passes between the plate fins 3a of the fin-tube heat exchanger 5a, exchanges heat with the heat medium, and becomes cold air or air. It becomes warm air and blows into the room.

At this time, since the cut-and-raised height of the cut-and-raised portion 2a provided on the plate fin 3a gradually decreases from the part near the cross-flow fan 7, the resistance coefficient of the airflow also becomes a sound source, and the cross-flow fan 7 The air flow caused by the rotation has a nearly uniform wind speed distribution regardless of the distance from the cross-flow fan 7, as shown by the arrows in FIG.

As a result, even the portion of the plate fins 3a that is far from the cross-flow fan 7 has sufficient air velocity, improving heat transfer performance, reducing the ineffective portion of the fin-tube heat exchanger 5a, and improving overall heat exchange. Your ability will improve.

In addition, since the wind speed distribution becomes almost uniform, the work of the cross flow fan 7 is reduced compared to the non-uniform wind speed distribution when the air volume is the same, and the rotation speed can be reduced, reducing power consumption and reducing noise levels. It will also decrease.

Effects of the Invention As described above, the present invention configures a fin-tube heat exchanger by decreasing the height of the cut-and-raised portion of the plate fin as the distance from the cross-flow fan increases. The air velocity distribution of the air passing through the fin-tube heat exchanger can be made almost uniform regardless of the distance between the fin and tube heat exchangers, and the heat transfer performance on the air side of the entire heat exchanger can be improved. In addition, by making the wind speed distribution uniform, the air-side pressure loss of the entire fin-tube heat exchanger is relatively reduced, and the work of the cross-flow fan is also reduced, resulting in lower power consumption and noise. We can provide air conditioners.

[Brief explanation of drawings]

FIG. 1 is a front view of a plate fin portion in a fin-tube heat exchanger according to an embodiment of the present invention, and FIG.
Figure 3 is a structural diagram showing the air distribution state of the air conditioner, Figure 4 is a front view of the bullet fin portion of a conventional fin-tube heat exchanger, and Figure 5 is the same. AA" cross-sectional view in Figure 4, and Figure 6 is a structural diagram showing the air distribution state of the air conditioner. 1... Heat exchanger tube, 2a... Cut-out portion,
3a...Plate fin, 5a...Fin tube heat exchanger, 7...Cross flow fan.

Claims (1)

[Claims] A fin-tube heat exchanger that has a large number of cut-out parts that disrupt airflow, and is formed by a large number of plate fins arranged in parallel at regular intervals, and multistage heat transfer tubes that pass through the plate fins. A cross-flow fan that forms an air flow through the fin-tube heat exchanger is provided near one end of the fin-tube heat exchanger, and the height of the cut-out portion of the plate fin is adjusted to match the cross-flow. An air conditioner that is lowered as it gets farther away from the fan.