Numerical/experimental modeling of a residential CST system and performance evaluation using ray-tracing method

On the brink of an energy revolution the world is facing, Concentrated Solar Thermal (CST) systems have emerged as a promising solution to address the dual challenges of energy security and climate change. This study presents a novel approach involving numerical/experimental modeling, sensitivity analysis, and optical evaluation of a residential CST system using ray-tracing method. In this study, a thermal dynamic model was developed in MATLAB and validated against experimental data. The experimental setup consisted of a parabolic dish with two reflective surfaces (aluminum foil and mirror) and an aluminum spiral collector. The findings indicate that the numerical model predicts water temperature with average deviations of 1.57% and 1.49% for the foil and mirror surfaces, respectively. Replacing the foil with a mirror increased water temperature by 28.5% (reaching 64°C) and achieved an optical efficiency of 67%. Monte Carlo ray-tracing analysis confirmed uniform energy distribution at the focal point with no hot spot formation. Furthermore, sensitivity analysis revealed that by doubling the reflective surface area, temperatures of 94.93°C and 62.73°C for the mirror and foil surfaces could be achieved, respectively.