256 Natural Frequency of Centrifugal Compressor Impeller in High Pressure Gas

Abstract

To predict natural frequencies of high-pressure centrifugal compressor impellers accurately, we measured the natural frequencies of an impeller vibrating in a high-pressure gas environment. In order to clarify the effect of gaseous species, we used four different gasses as the surrounding gas. It is known that natural frequencies of pump impellers in water decrease compared with their natural frequencies in air due to the added mass effect. However, in our experiments in a high-pressure gas environment, the natural frequencies of the impeller not only decreased but also increased compared with those conducting under atmospheric condition.