Numerical investigation of spray dehumidification process of moist air

This investigation focuses on the heat and mass transfer in dehumidification process of the moist air. The interaction of water droplets with the hot, moist air which is flowing in contrary to the water spray is studied in a chamber. Two dimensional and three dimensional simulations are performed in order to study the effect of various parameters on heat and mass transfer.The parameters such as droplet diameter,spray mass flow rate, droplet temperature,number of injections, spray cone angle, and spray location are considered. The results show that smaller droplets lead to higher humidity reduction at the outlet. However droplet size effect on temperature and relative humidity depends on the optimum radius. If droplets are smaller than optimum radius, increasing their size results in enhancement of heat transfer. On the other hand, if droplets are larger than the optimum radius, by increasing the droplet diameter heat transfer decreases. It is found that heat and mass transfer are proportional to mass flow rate of the spray. Furthermore results indicate that decreasing the coolant temperature causes humidity and temperature reduction at the outlet. In addition, spray cone angle effect is found to be negligible. Results demonstrate that using more sprays in the chamber helps to diffuse the droplets to regions close to the wall. It is concluded that location of the spray does not have significant effect on bulk temperature at the outlet.