The Comparison of Fixed and Variable Specific Heat Parameters Based on ANSYS-CFX

Abstract

At present, in the aerodynamic simulation calculation of turbocharger using ANSYS-CFX, we usually use a fixed constant for the gas performance parameters (including specific heat and thermal conductivity, etc.).In the whole calculation and analysis process, the selection of this constant value is defined according to the inlet temperature. This study found an appropriate, easy to operate and usable way to make the gas performance parameters in the calculation process change with different temperatures in different areas. In the calculation process, Ansys did call the temperature of different locations to calculate the specific heat value. In this study, we also checked the use of non-constant air performance parameters compared to the traditional fixed value on the turbocharger vortex end performance, the impact mainly includes flow, efficiency, and temperature.