Numerical Simulation of Hydraulically Actuated Natural Gas Compressors

A numerical simulation has been developed to assist in design of low-speed hydraulically actuated compressors delivering natural gas at overall pressure ratios of 90: 1. The model has been used to estimate the effect of heat transfer during compression, the effects of reduced inter-stage volume, and the effects of departures from ideal gas behavior during the last stage of compression. It estimates overall compression efficiency, volumetric efficiency and cylinder pressures as a function of time. The model is capable of estimating dynamic behavior in intercooler passages when inter-stage volumes are small, and has been adapted to two or three stages.