MAHLE Behr has developed a standardized workflow for simulating a virtual Temperature Cycle Test (TCT). This test is an integral part in the development process of indirect Charge Air Coolers (iCAC) and Exhaust Gas Recirculation coolers (EGR). Within this test, the cooler is charged with an alternating high and low heat load by varying the hot gas temperature and mass flow rate.
The transient CFD simulation is performed with STAR-CCM+ to model the flow of the fluids inside the cooler, the convective heat transfer between the fluids and the solid and the heat conduction within the solid. The result of the CFD simulation is the time dependent temperature distribution of the solid. The transient CFD results are carried over (“mapped”) to the FEA model within STAR-CCM+ and a FEA structural analysis is performed using PERMAS®. The result is the prediction of the local stresses and strain values which can be used as basis for the lifetime prediction of the cooler.
As a TCT simulation is a standard application within the development process, it has been completely standardized and partially automated including geometry preparation, meshing, physics setup, post-processing and mapping. An overview of this workflow is presented and the challenging aspects are discussed in detail.