Abstract: As the terminal equipment of underground water cooling system,mine air cooler is widely used in all kinds of high-temperature mines. In view of the low heat exchange efficiency and cooling capacity utilization of existing mining air coolers,the heat transfer process of surface air coolers is studied from the perspective of tube side and shell side by combining theoretical analysis and numerical simulation. The heat transfer performance of smooth tube air coolers and corrugated tube air coolers is compared,the influence of the wave crest height of the tube side and the arrangement of the shell side tubes on the comprehensive performance (heat transfer performance and flow resistance characteristics) of the mine air cooler is revealed. The results show that the corrugated tube air cooler has better heat transfer performance than the smooth tube air cooler. Changing the wave height can improve the heat transfer characteristics by about 24% ~ 135%,but also increase the flow resistance in the tube by about 176% ~ 767%. Among the five simulated wave crest heights,the bellows with a wave crest height of 3 mm has the best comprehensive performance,and reaches the best performance when the Reynolds number is 4 977,the comprehensive evaluation factor reaches the maximum value of 1. 27. Among the four kinds of pipe arrangement,the heat exchange can be increased by about 13% compared with the traditional in-line arrangement. The research results have certain reference significance for improving the heat transfer efficiency of mine air cooler and improving the high-temperature thermal environment underground.

Key words: mine air cooler,corrugated pipe,enhanced heat transfer,pipe arrangement,structural optimization