Abstract In this paper, aiming at the problems of low heat transfer efficiency and uneven heat transfer of heat exchange tubes in refrigeration and air conditioning chillers, a liquid ammonia spray cooling method is proposed, and a flow and heat transfer model is established. The distribution of refrigerant droplets in the fluid domain and the heat transfer on the surface of the heat exchange tube are simulated under different spray speeds, spray directions, and double nozzle sprays. The results show that with the increase of spray velocity, the heat transfer performance of heat exchange tubes decreases first and then increases. The effect of spray velocity on the heat transfer performance of each row of heat exchange tubes is not consistent. The farther away it is from the nozzle, the greater the speed corresponding to the peak value of the heat transfer performance improvement of the heat exchange tube will be; the spray direction (gravity) has little influence on the heat transfer performance of the heat exchange tube, which is within 5.1%. Compared with single-nozzle spray, double-nozzle spray greatly improves the heat transfer performance of multi-row heat exchange tubes.
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