Heat transfer aspects of natural convection over horizontal cylinder in liquid metal pool

The natural convection heat transfer from a horizontal cylinder placed in liquid metal pool is computationally investigated. The heat flux from surface of cylinder to the bulk liquid induces flow due to buoyancy. The effect of cylinder diameter, heat flux and bulk fluid temperature on the heat transfer coefficient is studied. The flow is computed using PHOENICS CFD software. The simulation is transient. The geometry is discretized using a 3D body fitted grid. The temperature variation of the cylinder along its periphery is computed from simulation. The validation of CFD results is performed by comparing the computed wall temperature variation with previously published experimental data. Excellent agreement of computed results with experimental data is observed for various heat fluxes. The heat transfer data is presented in the form of variation of Nusselt number with Gr · Pr2/(1+Pr). The heat transfer coefficient is found to rise slightly with bulk temperature. However, the cylinder diameter has a more significant effect on increasing heat transfer coefficient. Simulation data is generated by varying cylinder diameter, heat flux and bulk temperatures. Based on the data, a correlation is proposed. The correlation is shown to predict better compared to other correlations which were previously proposed. (author)