Experimental Study on Temperature Distribution and Heat Losses of a Molten Salt Heat Storage Tank
Xiaoming Zhang,
Yuting Wu,
Chongfang Ma,
Qiang Meng,
Xiao Hu,
Cenyu Yang
Affiliations
Xiaoming Zhang
MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation and Key Laboratory of Heat Transfer and Energy Conversion, Beijing Education Commission, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China
Yuting Wu
MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation and Key Laboratory of Heat Transfer and Energy Conversion, Beijing Education Commission, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China
Chongfang Ma
MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation and Key Laboratory of Heat Transfer and Energy Conversion, Beijing Education Commission, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China
Qiang Meng
State Key Laboratory of Advanced Power Transmission Technology (Global Energy Interconnection Research Institute), Changping District, Beijing 102211, China
Xiao Hu
State Key Laboratory of Advanced Power Transmission Technology (Global Energy Interconnection Research Institute), Changping District, Beijing 102211, China
Cenyu Yang
State Key Laboratory of Advanced Power Transmission Technology (Global Energy Interconnection Research Institute), Changping District, Beijing 102211, China
Two-tank molten salt heat storage systems are considered to be the most mature thermal storage technology in solar thermal power plants. As the key part of the system, the thermal performance of molten salt tanks is of great importance. An experimental thermal storage system with a new type of molten salt as a thermal energy storage medium has been built to investigate the temperature distribution of molten salt inside the tank during the cooling process from 550 °C to 180 °C. The temperature distribution of the salt was obtained, which reveals that temperature stratification appears at the bottom of the tank within the height of 200 mm. The position, with the maximum temperature difference of 16.1 °C, is at the lower edges of the molten salt storage tank. The temperature distribution was also measured to deepen our understanding of the insulation foundation, which shows that the maximum temperature appears at the middle upper part of the foundation and decreases radially. The heat losses of the molten salt tank were calculated by the classical equation, from which it was found that the heat loss decreases from 3.65 kWh to 1.82 kWh as the temperature of the molten salt drops from 550 °C to 310 °C. The effect of temperature stratification on the heat losses of the tank’s bottom was also analyzed.
