Experimental investigate on thermal properties of a novel high temperature flat heat pipe receiver in solar power tower plant

•A novel high temperature two-phase flat heat pipe receiver applied in solar power tower plants is proposed.•FHPR has good startup performance and isothermal property.•Input heating flux and inclination angle has a significant effect on the performance of the FHPR.•FHPR ensure long term safe and stable within a certain range of heating power operation.

The high temperature two-phase flat heat pipe receiver (FHPR) is placed in solar power tower plant, which can achieve the uniform heat flux distribution and remove heat spots. This paper presents an experimental study of heat transfer performance of a FHPR. While liquid sodium (Na) shows potential for solar thermal power systems due to its wide range of operation temperatures, a simple receiver sample filled with liquid Na was developed. A series tests were performed to investigate the influences of input heating flux and inclination angle on FHPR thermal behavior. The experimental investigations were also conducted to validate the performance of fast response characteristics. The results indicated that high temperature FHPR has good startup performance and isothermal property, input heating flux and inclination angle has a significant effect on the performance of the FHPR. It also can effectively prevent thermal stress and heat spots. Based on these studies, guidelines are provided for its installation in high-temperature concentrated solar thermal central-receiver systems for power generation.