AUTHOR=Ji Guo-Jian , Gu Jin-Ming , Chen Zhi , Lu Bei-Bei , Gao Ying 

TITLE=Experimental research on heat transfer characteristic of HITEC molten salt in evacuated tube solar collector

JOURNAL=Frontiers in Energy Research

VOLUME=Volume 11 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2023.1150326

DOI=10.3389/fenrg.2023.1150326

ISSN=2296-598X

ABSTRACT=HITEC molten salt is an adequate heat transfer fluid. HTF in evacuated tube solar collector (ETSC) is employed in parabolic trough collector (PTC) for solar power generation. Enhance flow and heat transfer performance are essential for practical application of HITEC in ETSC, which was studied experimentally with varied operating temperatures and mass flow rates. The empirical formula for Nu in correlation with Re from 13204 to 29258 was fitted with the error ranging from -14.4% to 19.2%, based on the temperature of HITEC salt flowing in ETSC from 473K to 573K. The experimental correlation of Nu shows that the study provides a theoretical foundation for the industrial application of HITEC for heat transfer in concentrated solar power (CSP) system. Compared with different solar radiation, heat loss of ETSC can be compensated by the thermal energy absorbed with solar selective coating. The effective thermal energy is calculated to be 190.28 W under the steadily experimental solar irradiance of 700 W/m2.