The Effect of the Configuration of the Absorber on the Performance of Flat Plate Thermal Collector

In this study, a numerical thermal analysis for a new designed flat plate thermal collector was conducted through modeling. The new flat plate thermal collector has ellipse shaped tubes inside a wavy shaped absorber, which is made of stainless steel. For the comparison, the conventional flat plate thermal collector with circular copper tubes served as a base case was also modeled. Hottel-Whillier equations were utilized to formulate thermal networks for both models developed in Engineering Equation Solver. According to simulation results, for a given solar radiance, the thermal efficiency of both solar collectors decreases along the increase of the operating temperature of the fluid. Given a same operating temperature of fluid, higher solar radiances lead to higher efficiency of both thermal collectors. Comparably, the new flat plate thermal collector generally obtains a 10% higher efficiency than the conventional one at different solar radiance level and average operation temperature of towing to its new design of the absorber. This concludes that the new flat plate solar collectors would be a better option for typical solar domestic hot water system