Influence of different design parameters on side channel compressor performance

Abstract

Only few design guidelines for side channel compressors are published in open literature. Among those the most common ones are from Grabow, Surek, and Raheel. In this publication we focus on the design guideline of Grabow, which includes, among several analytical equations, two empirical estimates for head coefficient and blade angle. These estimates lead to an uncertainty in the design process and could potentially effect the performance curve of the machine. Therefore, five side channel compressor geometries are designed based on Grabow with different estimates for head coefficient and blade angle in order to assess their influence onto the compressor performance. Those designs are the input parameters for transient CFD simulations to compute total pressure ratio and isentropic efficiency. The results indicate that higher head coefficient during the design process lead to a higher total pressure ratio, in particular for lower flow rates. Similarly, a higher blade angle also increases the total pressure ratio and furthermore reduces the flow circulation in the side channel. In general, influence onto isentropic efficiency is much weaker, though.