Performance study of finned tube evaporative air cooler based on experiment and numerical simulation

摘要

The influence of air speed, spray density and tube bundle on wet air cooling of the fins are analyzed through numerical solution. The spray water droplets are released from the surface injection source in the discrete phase model (DPM). And the water film is formed in three-dimensional fins using Eulerian wall film model (EWF). The species transport model is coupled with EWF model to solve the phase transition and heat exchange. The heat exchange and pressure loss of tube bundle are evaluated through field synergy principle and Fanning friction factor, and a comprehensive performance factor and mass transfer coefficient of 57mm fins are higher than that of other two fins under varied air flow rate and spray density. Besides, The increase in tube rows number weakens the mass exchange of unit area. When the Re exceeds 2,820, the comprehensive performance of finned tube bundle with more rows become worse.