Numerical study on convective heat and mass transfer of plain fin in wet conditions

A 3D numerical model of convective heat and mass transfer is presented for plain fin in wet conditions. The heat and mass transfer characteristics of plain fin under dry and wet conditions are compared with the Reynolds number ranging from 190 to 3770 and the air inlet relative humidity ranging from 50% to 90%. Results show that heat transfer coefficient under wet conditions is 2.8~3.1 times higher than that under dry conditions, and the dry fin efficiency is about 35.8~41.9 percent higher than the corresponding wet fin efficiency. When the plain fin is in the partially wet conditions, the wet fin efficiency increases with increase of inlet relative humidity, whereas the heat transfer coefficient decreases with increase of inlet relative humidity. When the plain fin is in the fully wet conditions, the effects of inlet relative humidity on the wet fin efficiency and heat transfer coefficient are very small.