Flow simulation with conjugate heat transfer, which involves fluid flow, conduction, and radiation within solid components, is a vital capability that enables engineers to design and assess cooling systems for heat-producing parts such as brakes, powertrains, batteries, and power electronics in both gasoline and electric vehicles.
In this study, we employ PowerFLOW®, which features a thermal solver capable of simultaneously modeling both fluid and solid domains within a unified framework. The fluid flow is simulated using the Lattice Boltzmann Method (LBM) with VLES turbulence modeling based on the RNG k–ε approach. The solid domain is solved using a finite volume method with second-order accuracy for thermal conduction, combined with surface-to-surface radiation modeling for thermal exchange between surfaces. This integrated approach streamlines the simulation workflow while enabling accurate representation of both conduction and radiation phenomena.
We assess the accuracy of the conjugate heat transfer (CHT) simulation methodology for both forced and natural convection benchmark cases. For the forced convection case, channel flow with heated mounted cubes was analyzed, while for the natural convection case, a simplified engine bay under soak conditions was simulated. In both configurations, the simulation results showed good correlation with experimental data, demonstrating the reliability of the CHT approach.