Technological improvement on energy-efficient methods applied to a solar cavity collector

An advanced and improvised version of a flat plate collector is the solar cavity collector (SCC). The experimental analysis of an SCC with various working parameters is presented in this research paper. Overall dimensions of the SCC are 1.25 × 0.85 × 0.05 m. Initially, SCC has been tested with aluminium and copper as receiver materials. Various length to diameter ratios [L/D ratio] have been experimented viz., 40, 50, and 78.74. Comparisons have been made for its optimal performance with circular and rectangular type cavity and also with cavity cover materials. Pebbles are used in SCC for the improvement in heat exchange as a sensible heat storage material. Further to achieve improved heat transfer rates between the cavity and the transport fluid (water), heat transfer fluid [HTF] has been incorporated in SCC. It has been tested with different mass flow rates of water such as 0.002, 0.0025, 0.003, 0.0035, 0.004, and 0.0067 kg/sec to investigate and find its optimal performance parameter. Copper used as a receiver material gives better performance than other materials. HTF is considerable for larger mass flow rates of water.