EXPERIMENTAL STUDY TO EVALUATE THE THERMAL PERFORMANCE OF MULTI STAGE PARABOLIC TROUGH SOLAR COLLECTOR USING A TWISTED ABSORBER TUBE

Abstract

This study investigates the performance of two collectors from parabolic trough solar collectors for moderate heated water production. The goal to enhance thermal energy storage, boost heat transport, and maximize efficiency in order to boost performance. of parabolic trough solar collectors. Through experimental study under three distinct mass flow rates, it also looks into the effects of twisted tubes and external conditions (pollution, wind). Because of its high specific heat capacity, which enables it to store and transfer significant amounts of thermal energy, water is utilized as a working fluid. Its availability, affordability, low viscosity, and good thermal conductivity all contribute to its safety and environmental friendliness while also lowering pressure loss and improving heat transfer efficiency. Two solar energy-collecting devices of the parabolic trough type (PTC) were constructed, run, and assessed. In this study, the effectiveness of a set of PTC devices with a combined aperture area of 3.24 m² for both collectors was evaluated. Stainless steel sheet are uitilized to coat the parabolic trough. Copper twist tube absorbs heat . The exterior and inside diameters are 0.0125 meters and 0.0105 meters, respectively. The volume flow rate of water used as a heat transfer medium was 2, 4, 6 L/min. The thermal efficiency, usable heat, and alternative measures of The parabolic trough solar collector's efficiency ,were calculated. and exit temperature experimental and an evaluation of the outcomes of experiments between the three cases was made and the work also included the determination of the coefficient of heat transfer, pressure drop, for insert in parallel flow. The results showed a rise in pressure drop because of the high friction resulting from the bends. The experiments outdoor measures were used to evaluate the immediate thermal efficiency and usable heat gain. The impacts of ambient circumstances, collector temperature at the input and mass flow rate of the working fluid ,were examined in the PTC array's performance investigation. With a non-evacuated glass cover, solar collectors operated at a maximum inlet temperature of 78.5,70,66.4 °C and an exit temperature of 80.5,71.9,68.7 °C sequentially at a 6 l/min flow rate under turbulent flow conditions, achieving maximum efficiencies of almost 40%, 29%, and 13%. The collector's efficiency formula, which was obtained from this investigation, is in good agreement with previous publications.