Influence of water injection parameters on the performance of a water-lubricated single-screw air compressor

Abstract

A thermodynamic model of a water-lubricated single-screw air compressor was established to examine the impact of water injection parameters on performance. Heat transfer and leakage between humid air and water was considered by analyzing the impacts of rotation speed, discharge pressure, the rate of water injection, and diameter of droplets on the performance of a compressor. The discharge temperature could be reduced by increasing the rate of water injection, resulting in the compression procedure moving towards an isothermal state. The increase in the rate of water injection under rated conditions from 60 L/min to 80 L/min resulted in a reduction in the compressor discharge temperature, increased the volume efficiency, and increased adiabatic efficiency by 11.1 K, 1.5 %, and 2.8 %, respectively. Water injection atomization increased the area of transfer of heat between humid air and water and improved the performance of compressor.

Numerical Investigation of an Oil-Free Liquid-Injected Screw Compressor with Ammonia-Water as Refrigerant for High Temperature Heat Pump Applications

“…It can be concluded that the injection rate and ratio must be adapted and controlled according to the compressor speed. These observations are consistent with the results presented in the literature by various authors such as Tian et al [22], Wang [39] and Li et al [44].…”