Experimental investigation on the heat transfer performance of molten salt flowing in an annular tube

Abstract

This paper investigated the heat transfer performance of molten salt steam generator used in the solar power tower plant and testified the validity of the well-known classical heat transfer correlations and four new convective heat transfer correlations. Various experiments on the heat transfer performance of molten salt with high pressure water/steam in a horizontal tube-in-tube have been carried out on the test-bed under the inlet molten salt temperature of 400 °C/450 °C/500 °C and the inlet water/steam temperature of 300 °C/390 °C, respectively. The experimental results showed that the range of the Nusselt numbers of molten salt is 40–70, and the inlet molten salt temperature played an important role in heat transfer of molten salt and water/steam. However, the effect of the pressure of water/steam was slight. In addition, based on the experimental data, good agreement was observed between the experimental data of molten salt and part of classical and new correlations. Finally, the fitted forced convective heat transfer correlations of molten salt were obtained by using multiple linear regressions within a deviation of ±10%.