Abstract

The presently applied desulfurization technologies require a supply of air through centrifugal compressors realizing the pressure increment on the level of 150–200 kPa. Taking the necessary mass flow rate of the processed air into account it is necessary to increase the efficiency of the compression process realized in these machines. The paper will include the results of the works related to the analysis of the gas flow in the compression stage operating with two impellers. The first one has been described with a mathematical function preserving the condition of ruled surface and the geometry of the other impeller has been modeled according to the shape of the meridional velocity profile in the inlet section thus forming leading edge. The common feature of
both impellers is the same mathematical function that describes the meridional section and the profile of the blade. The outer diameter of each of the impellers is 200 mm and the blade angle in the outlet section 45◦. The compression stage reaches the pressure ratio of 1.4 at the nominal mass flow of 0.73 kg/s maintaining the impeller rotational speed on the level of 24 400 rpm. For the evaluation of the operating parameters and the nature of the gas flow in the compression stage operating with two impellers computational fluid dynamics simulations were carried out and experimental research has been performed using laser Doppler anemometry for impeller of ruled surface.