Enhancement of mixed convection heat transfer in a three-dimensional horizontal channel flow by insertion of a moving block

Enhancement of mixed convection heat transfer rate of a heat surface in a three dimensional horizontal channel with insertion of a moving block is studied numerically. Bossinique assumption is not adopted, then methods of Roe scheme, preconditioning, and dual time stepping are needed to solve the governing equations. Contributions of important parameters of Gr/Re² and moving block velocity to the heat transfer rate are validated. Due to the consideration of natural convection, under situations of large magnitude of Gr/Re² a counter-effect for promotion of heat transfer rate is observed. Oppositely, under situations of small magnitude of Gr/Re², the enhancement of heat transfer rate is remarkably achieved.