Performance comparison of evacuated U-tube solar collector integrated parabolic reflector with conventional evacuated U-tube solar collector

In the present study, performance of the fabricated evacuated U-tube solar collector integrated parabolic reflector (EUSCIPR) and conventional evacuated U-tube solar collector (CEUSC) are analysed experimentally. With reference to humid climatic conditions, a 3D model is developed for comparing the thermal performance of EUSCIPR with a CEUSC. Developed model is validated with field test data and found in good agreement among them. Heat transfer fluid (HTF) temperature difference, energy intake/heat gain and thermal efficiency of the solar collectors are investigated experimentally at various ambient temperatures and solar intensities. From the experimental investigations, it was observed that, in a sunny day, the energy losses incurred across the solar collectors was high during peak hour (1: 20 PM). From the numerical studies, it is found that within the given operating range, the thermal efficiency of the EUSCIPR is 14.1% higher than CEUSC. Further, for a given inlet condition, the contour plots for variation of HTF temperature along the U-tube of EUSCIPR and CEUSC are predicted numerically, and the obtained results are discussed in detail.