Convective heat transfer of molten salt in the shell-and-tube heat exchanger with segmental baffles

•A flow layout applied in laboratory to test molten salt in STHE shell is designed.•Transitional HTPs of molten salt (209.41-241.49 °C) in STHE-SBs shell are analyzed.•Empirical heat transfer correlations of molten salt in STHE-SBs are fitted.•Validation of traditional correlation applied in molten salt STHE-SBs is conducted.•Heat transfer enhancement in molten salt STHE-SBs is discussed.

In this paper, a special flow layout with U-shaped tubes applied in the laboratory was designed for testing the heat transfer performances (HTPs) of molten salt in the shell side of a shell-and-tube heat exchanger (STHE). Based on this design, the transitional convective HTPs (6142 < Re < 9125) of molten salt with higher temperature (209.41-241.49 °C) in the STHE with segmental baffles (STHE-SBs) were experimentally studied, and the corresponding heat transfer correlations were fitted. Then the validation of the traditional correlation applied in the molten salt STHE-SBs was conducted. Finally, the comparison of heat transfer enhancement in the molten salt STHE-SBs was discussed. The results show that a good agreement with 2% deviations exists between the fitted correlations and the test data. Meanwhile, the traditional Kern correlation, with a 7.1% maximum deviation compared with the test data, is still appropriate to analyze the HTPs of molten salt STHE-SBs. The effects of segmental baffles on the molten salt heat transfer enhancement in lower flow rate region are better than those in higher flow rate region, and the maximum increment of Nusselt number is 26%.