Study on Thermal Flow Field of a Turbocharger Centrifugal Compressor

Abstract

The numerical study on the thermal flow field of a centrifugal compressor, installed in automotive turbochargers, has been conducted for attaining high reliability thermal and structural design. CHT (Conjugate Heat Transfer) calculations, working for simulating heat transfer with mutual dependence between solid structures and fluid, were applied to a turbocharger centrifugal compressor. The detailed modeling of the centrifugal compressor includes a back cavity and stationary parts behind the wheel, which simulates the thermal flow field induced by a rotor-stator system. In conjunction with the CHT calculations, the detail temperature field has been acquired in bench tests. Local temperatures of the stationary parts were measured by sheathed thermocouples. All measured temperatures are in good agreements with numerical ones from the CHT Calculation. As a result, the evaluated temperature field of the compressor wheel can be reliable. In addition, thermal and flow phenomena of the centrifugal compressor have been clarified in case that the mass flow rate of radial inflow varies at the back cavity.