Parallel simulation of engine in-cylinder processes with conjugate heat transfer modeling

A conjugate heat transfer (CHT) model is implemented into KIVA-4 to simultaneously solve the engine in-cylinder dynamics and temperature field in solid engine components, according to the balances of heat flux and temperature on fluid-solid interface. To mitigate the increased computational demand due to CHT modeling, a vertical partition scheme is proposed for sector engine cylinder mesh with solid-phase grids to allow parallel computation based on MPI. Using the resulting parallel program, multicycle simulation of diesel engine spray and combustion is performed for various operating conditions and using different numbers of processors. Results indicate that the CHT modeling produces a realistic temperature distribution on chamber wall and has a strong impact on the simulation of in-cylinder dynamics, compared to the traditional assumption of constant wall temperature. With certain number of processors, the present partition scheme shows reasonable scalability and effectively reduces the computer time of simulation.