Development of correlations for the heat losses from the receivers of modular CSP plants with central tower

The analysis in this work is based on a sodium cooled, billboard type receiver adopted in CSP plant for Jemalong (Australia) Solar Thermal Station. It is aimed to evaluate the convective heat losses for the irrational surface of the receiver by using 3D computational fluid dynamics (CFD). The computational results for free convection are first being analyzed when imposing different uniform surface temperature for the receiver and a correlation procedure based on dimensionless Nusselt number on dependency of Rayleigh number is conducted. Then simulations for pure forced convection under different wind direction and intensity are being set up with gravity off and directional wind effect on heat losses has been analyzed. The correlation procedure for evaluating convective heat losses is done after determination of characteristic length by observing temperature and velocity fields around the receiver. A discover of similar dynamics behavior regarding supplementary incidence angle has been revealed. At the end, a mixed convection analysis is made to verify the accuracy of obtained correlations by comparing the results of heat transfer coefficient between that calculated from correlation and that from simulations.