Numerical Simulation of Spray Cooling Gas with High Temperature and Velocity in Compressor Inter-Stage

Abstract

To investigate the effects of nozzle number, spray parameters, airflow velocity and airflow temperature on cooling efficiency of airflow, a numerical simulation of the water jet cooling in the compressor is carried out in a simplified three-dimensional model, about the preliminary study of compressor inter-stage cooling technique. The results showed that increasing the number of nozzles could promote the mixing of the gas and droplet further to improve the evaporation efficiency. The heat transfer temperature variations are increasing with the gas temperature rising. It showed that 8 % improvement in evaporation rate was achieved by increase gas temperature from 383 K to 413 K. Smaller droplets evaporate faster because they provided more surface area per unit volume than larger droplets, and 20 % improvement in evaporation rate was achieved by decreasing droplet diameters from 40 m to 20 m. When the inlet flow velocity was small, the droplet evaporated for more time and the evaporation rate is higher, which can improve the cooling effect by increasing the spray cone angle and raising the initial droplet velocity. As the inlet flow velocity decreased from 100 m/s to 25 m/s, the evaporation rate could reach 80 %.