Research on the influence of highly loaded design method on the stability of helium compressor

Abstract The highly loaded design method of helium compressor can effectively resolve the problem of helium compression in high temperature gas cooled reactor (HTGR). However, the alteration in design method has led to the variation of its characteristics at the same speed. In order to resolve this issue, in this paper, a three-dimensional, multi-passage unsteady numerical analysis is conducted to develop the understanding of the performance of a 1.5 stages highly loaded helium compressor. At first, the influence of the highly loaded design method on the unsteady flow of helium compressor is analyzed at the design point. Then, the instability characteristics of highly loaded helium compressor are studied by analyzing the flow field near stall point. Finally, the main factors causing the instability of highly loaded helium compressor are discussed. The result shows that radial separation which is caused by the inverse pressure gradient at the stator root is the main factor causing instability in highly loaded helium compressor.