ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-472-4
ISBN Online: 978-1-56700-471-7
3rd Thermal and Fluids Engineering Conference (TFEC)
COVECTION HEAT TRANSFER PERFORMANCE OF SOLAR SALT WITH A HIGH MELTING-POINT IN A CIRCULAR TUBE
Abstract
Molten salt is a useful energy storage medium in solar power system. In order to explore convective heat
transfer performances of solar salt with the subcritical water, the heat transfer performance of solar salt with
a high melting-point (220°C) in a horizontal double-pipe heat exchanger was investigated by using solar salt
and subcritical water as the working mediums. Based on the experimental data, a heat transfer correlation
about the Nusselt number of solar salt was obtained by using multiple linear regressions; the resulting
Nusselt value was then compared to the values obtained via classical convective heat transfer equations.
Results of the comparison suggested that the fitted Nusselt number correlation model was able to accurately
describe the heat transfer between solar salt and subcritical water within deviation of ±10%.Conversely,
comparing the experimental results to those obtained via classical convective heat transfer equations, such as
the Dittus-Boelter equation, Sieder-Tate equation, Miheev equation, and Gnielinski equation, yielded
significantly large deviation (maximum: -20% to -40%). Heat transfer of solar salt was found to be
moderately affected by the inlet temperature, whereas the effects of the subcritical water pressure within the
inner pipe were minimal.