Abstract
The present paper deals with the numerical investigation of piston-driven heat transfer and fluid flow in a cylinder containing a sudden expansion. The calculation procedure employed is based on a control-volume-based finite element method for incompressible flow with a staggered and moving grid and SIMPLER algorithm for pressure-velocity coupling. The numerical results show a good agreement with the experimental data reported in the literature. Results concerning time and space evolution of the thermal and flow fields downstream and upstream of the sudden expansion are presented for different values of the expansion ratio, the initial clearance volume, and the piston velocity. The effects of these parameters on the instantaneous convective heat flux and on the total convected heat are also evaluated at the sudden expansion section.