Numerical analysis of the scavenge flow and convective heat transfer in large two-stroke marine diesel engines
Abstract
A novel computational fluid dynamics (CFD) model is presented for the study of the scavenging processand convective heat transfer in a large two-stroke low-speed uniflow-scavenged marine diesel engine.The engine is modeled using a fully resolved 12 sector, corresponding to one scavenge port, with cyclicboundaries in the tangential direction. The CFD model is strongly coupled to experiments and effectivelyprovides a high order ‘‘interpolation’’ of the engine processes through the solution of the Reynolds-AveragedNavier–Stokes (RANS) equations subject to boundary conditions obtained through experiments. Theimposed experimental data includes time histories of the pressure difference across the engine and theheat release during combustion. The model is validated by a numerical sensitivity analysis and througha comparison of model predictions and experimental data, which shows a good agreement. The resultsshow an effective scavenging and a low convective heat loss in agreement with experimental data forlarge marine diesel engines.© 2014 Elsevier Ltd. All rights reserved.