Heat transfer tube for evaporator and method of manufacturing same

Abstract

The invention relates to a heat transfer pipe for an evaporator and a production method thereof. The heat transfer pipe is provided with a pipe body with an inner cavity, and fins arranged on the peripheral surface outside the pipe body and spirally distributed along the axial direction of the pipe body. Lateral walls of the fins incline from the bottoms of the fins towards the outside of the tops facing the fins. Empty cavities, the opening sections of which are less than the bottom areas, are formed between adjacent fins; and the bottom surface of each empty cavity is also provided with a first groove and a second groove crossed with the first groove, at least either the first groove or the second groove comprise a plurality of grooves, and the first groove and the second groove have a plurality of crossing nodes. The first grooves, the second grooves and the nodes of the first and the second grooves have worse moisturizing property than the bottoms of the empty cavities so that activation energy or superheat degree of foam generation and growth can be reduced, more gasification core points can be formed, and more foams can be formed so as to improve boiling heat exchange capability. The pipe-outside boiling heat exchange efficiency of the heat transfer pipe is higher than a conventional heat transfer pipe with smooth empty cavity bottom by 7-12 percent.

Description

technical field [0001] The invention relates to a heat transfer tube for an evaporator and a manufacturing method thereof. Background technique [0002] Heat transfer tubes are often used in evaporators, such as flooded evaporators in chillers in central air conditioning systems. The heat transfer tube includes a tube body with an inner cavity, fins formed on the outer wall of the tube body that are helically distributed along the tube body axis, and grooves formed on the tube inner wall that are helically distributed along the tube body axis. In the process of processing, the top of the fin is evenly distributed along the spiral direction of the fin, and a boss is formed between adjacent cuts on the same fin, and the boss is mechanically rolled so that the boss extends to both sides of the fin to achieve The degree of mutual contact with the adjacent fins finally forms a cavity with a small upper opening and a large space below (the bottom surface of the cavity is the oute...

AI Technical Summary

Problems solved by technology

[0004] Although the fin structure can enhance the heat transfer capacity of the heat transfer tube, the fluid boiling heat transfer coefficient in the cavity is not high, which still limits the heat transfer capacity of the heat transfer tube

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