In Iraqi climatic conditions, the solar collector systems are characterized by high degradation in thermal performance that is a result of poor selection of tilt-angle, high dust deposition, high ambient temperatures, aerosol loading, and strong seasonal variations in solar irradiance. These drive down solar radiation absorption, behavior in heat transfer, and overall energy efficiency, and conventional fixed-angle optimization cannot guarantee long-term stable performance in hot-arid environments. In this paper, the researcher suggests an integrated heat-transfer and optimization model to be used to determine optimum annual and monthly tilt angles to solar collectors at Baghdad. The model is a combination of solar geometry relations, including the beam radiation ratio (Rb) and total tilted irradiance (HT), and equations of thermal energy balance that include the convective and radiative heat transfer. Particle Swarm Optimization (PSO) and Gay Wolf Optimizer (GWO) are two metaheuristic algorithms that are used to optimize tilt-angle scheduling under different environmental conditions. The results of simulation indicate that the optimal annual tilt angle is around 29 ° C with the best monthly tilt being close to 0 ° C in June-July and 59 ° C in December. The monthly optimized approach enhances performance in terms of thermal performance by approximately 12-15% and sensitivity to short-term fluctuations in irradiance and ambient temperature as compared to fixed-tilt systems. The proposed framework offers a convenient balance between simplicity and adaptability, providing better performance without the complex tracking systems and enabling application scale ability to solar thermal systems, PV/T systems, and hybrid systems.
Alaskaree et al. (Fri,) studied this question.