Effect of External Heat Transfer and Thermal Boundary Conditions in Rigid-Free Top Facing Cavity
In the present study, the numerical results of natural convection due to heat transfer occurring from a 2D top facing open cavity are analyzed. The bottom surface of the cavity is at higher temperature compare to the top surface. The different combinations of the thermal boundary condition at the vertical side walls are studied. The free slip boundary conditions with external heat transfer coefficient are applied at the top surface of the cavity. The external heat transfer is included to make these phenomena more relevant for various applications. The present analysis is carried out using different non-dimensional parameters, namely, Rayleigh number, aspect ratio and external heat transfer coefficient (External Nusselt number). The convective heat losses for the aforesaid conditions are evaluated. Based on the grid and time independence study a 100×100 grid with 21.06 non-dimensional time step size is used for the computations. Significant effects of the thermal boundary condition are observed in term of the convective heat transfer through the bottom surface of the cavity. However, in some cases the effects of the external heat transfer with respect to the aspect ratio are negligible. In addition to this, the dependencies of the convective heat transfer with its infusing parameters are also observed n term of the correlation.