Heat exchange system and heat exchanger thereof

Abstract

The invention provides a heat exchanger comprises at least two layers of heat exchanger fins, each layer of heat exchanger fins comprises a lower collecting pipe, an upper collecting pipe, a plurality of microchannel flat tubes connecting the upper collecting pipe and the lower collecting pipe, and fins disposed among the microchannel flat tubes. The lower collecting pipe of the first layer of heat exchanger fins is provided with a refrigerant inlet tube, the upper collecting pipe of the last layer of heat exchanger fins is provided with a refrigerant outlet pipe, a connecting channel is disposed between an upper collecting pipe of a former layer of heat exchanger fins and a lower collecting pipe of a later layer of heat exchanger fins, a refrigerant pass through the connecting channel from the former layer of heat exchanger fins to the later layer of heat exchanger fins, and the refrigerant flows from the lower portion to the upper portion in the microchannel flat tubes of each layer of heat exchanger fins. According to the heat exchanger, the refrigerant flows from the lower portion to the upper portion in the microchannel flat tubes of each layer of heat exchanger fins, so the heat exchange performance of the heat exchanger can be raised.

Description

【Technical field】 [0001] The invention belongs to the field of heat exchange, in particular to the field of multilayer parallel flow heat exchangers. 【Background technique】 [0002] As a heat exchange device, heat exchangers are used in many fields that require heat exchange, especially in air conditioners, where heat exchangers are an important part of air conditioners. Among them, because the parallel flow heat exchanger has the characteristics of high cooling efficiency, small size, light weight, and strong pressure resistance, parallel flow heat exchangers are increasingly used in air conditioners. [0003] The parallel flow heat exchanger is mainly composed of microchannel flat tubes, cooling fins and headers. There are headers at both ends of the microchannel flat tubes for distributing and collecting refrigerant. Corrugated or louver-shaped cooling fins are arranged between adjacent microchannel flat tubes to enhance the heat exchange efficiency between the heat exc...

AI Technical Summary

Problems solved by technology

[0007] In the existing multi-layer heat exchanger, when the refrigerant enters the header 5' from the header 4' and then flows from the header 5' to the header 6', it flows from top to bottom, because the header The refrigerant in the tube 5' is a mixture of gas and liquid. When the refrigerant flows downward from the header 5', the liquid refrigerant will flow downward more easily due to gravity, while the gas refrigerant will flow downward due to the gravity. It is lighter in weight and tends to move upwards. At this time, the liquid refrigerant and gaseous refrigerant will form a blockage in the header 5', resulting in poor flow and affecting heat exchange efficiency.

In addition, when the refrigerant flows from the header 5' to the header 6' from top to bottom, the liquid refrigerant may directly flow from the center of the inner cavity of the microchannel flat tube 8' due to the effect of gravity. The upper header 5' drops directly to the lower header 6'. At this time, the liquid refrigerant is not in contact with the cavity wall of the microchannel flat tube channel 8' of the heat exchanger, and the gaseous refrigerant is squeezed to the The inner cavity wall of the microchannel flat tube 8' is in contact with the microchannel flat tube channel of the heat exchanger to exchange heat with the surrounding air. When the liquid refrigerant does not contact the cavity wall of the microchannel flat tube channel, it directly falls When it reaches the lower header, the heat transfer effect of this part of the liquid refrigerant is greatly reduced, so the heat transfer effect is not ideal, which reduces the heat transfer performance of the heat exchanger

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