Experimental investigation of a small-sized centrifugal compressor for a closed-brayton cycle gas turbine power system

An experimental characterization of small-size centrifugal compressor for turbine-driven generator-compressor unit of a closed-Brayton Cycle gas turbine power plant is presented. Operating fluid is a mixture of inert gases. Bench equipment (replacement of pressure sensors and systems for collecting and processing signals) was upgraded for characterization to complete control of research. The paper describes the test facility, the equipment used and the method of research performance. Test runs were carried out in air compressor, with a cover of the throttle before the surge. Comparison with the calculated point restated at the speed of the experiments (30 000 rev / min) is presented. The influence of the physical properties of the working fluid on the performance of a centrifugal compressor at the calculated pressure ratio (1.75) is evaluated. Experimental research on Xenon and helium mixture (molar mass of argon) and argon at full throttle and varying speeds from 23700 to 30300 rpm is presented.