Enthalpy Determination Methods for Compressor Performance Calculations

Abstract

In the field of compressor performance simulation and measurement, the most commonly used method to evaluate compressor performance is based on the analysis of inlet and discharge pressures and temperatures. Combined with gas mixture properties and known mass flow rate, it is a simple process to determine overall compressor power and efficiency. However, the critical step in this process is the conversion of pressure, temperature, and gas property information into both actual and ideal enthalpy differences. In addition to the abundance of equation of state (EOS) formulations, there are also multiple methods commonly applied for the calculation of the enthalpy differences. This paper reviews several of the methods used for this critical calculation and provides a comparison using multiple gas compositions.