Study on the influence of spray characteristics and air flow direction on heat transfer of spray evaporative condenser

Abstract

Spray cooling is effectively utilized in evaporative condensers to achieve efficient heat and mass transfer transmission, while also effectively preventing performance degradation caused by packing blockage. The heat transfer efficiency is strongly affected by the relative flow direction between the spray and air flow. This work employs computational fluid dynamics to evaluate and examine the heat transfer effects of parallel and countercurrent air and spray flow in evaporative condensers. The findings indicate that increasing spray density and wall temperature enhances heat transfer efficiency. Smaller droplets with lower initial velocity exhibit superior heat transfer capabilities in parallel flow, while smaller droplets also perform well in countercurrent flow as long as the initial velocity is not too high. Additionally, a slight increase in air velocity improves heat transfer efficiency in both parallel and countercurrent flow conditions. It is important to note that the countercurrent condition has a larger heat transfer effect than the parallel flow.