Study of Aerodynamic Performance of an Air Compressor Model Stage Used for Different Real Gases

doi:10.3901/JME.2016.08.198

Abstract

Abstract: Based on the criterion of similarity i.e the machine Mach number is kept equal, numerical simulations of aerodynamic performance are carried out for a centrifugal compressor model stage when used for air and different real gases at normal and high temperature and pressure. Except for air, two heavy working fluids including carbon dioxide and propylene and one light fluid i.e. methane are considered. Major impact factors on stage aerodynamic performance need to be found by analyzing physical properties of different gases and stage performance. Numerical results show that the specific heat ratio has a large influence on the flow field of the compressor stage when the machine Mach number is kept the same and the status of a fluid is far away from its critical state. Hence the stage aerodynamic performance of different real gases vary with specific heat ratio. Internal flow loss and pressure become large with increase in specific heat ratio. When the difference of specific heat ratio between inlet and outlet is small, the stage efficiency becomes lower and pressure ratio gets larger as the specific heat ratio becomes higher. However the head coefficient of stage changes slightly. When the difference of specific heat ratio between inlet and outlet is large, the stage performance largely varies.

Key words: centrifugal compressor, high temperature and pressure, numerical simulation, real gas, specific heat ratio

CLC Number:

TH452

LIU Yan, TAO Lihua, WANG Jian, WANG Hailun, SUN Yuying. Study of Aerodynamic Performance of an Air Compressor Model Stage Used for Different Real Gases[J]. Journal of Mechanical Engineering, 2016, 52(8): 198-206.

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