Energy and exergy analysis of a glazed solar preheating collector wall with non-uniform perforated corrugated plate

Abstract

The solar preheating wall provides an effective solution to the conflict between the requirement for fresh air and the need for heat conservation in winter by preheating fresh ventilation air. In this paper, a study of the glazed solar preheating collector wall is carried out by numerical simulation with the aim of improving heat collection efficiency through structural optimization. The influence of the environment as well as its range of applications are investigated. The characteristics of the internal flow and temperature distribution are obtained to facilitate the structural analysis. The influence of air volume and structural parameters on thermal efficiency is investigated, providing a good reference for structural design optimization. In addition, it is observed that the exergy efficiency of the optimized design is 1.3 times higher than that of the conventional solar wall, while the thermal efficiency is 15% higher than traditional ones. The heat loss rate is reduced by 40% in high wind and extremely cold regions compared to that of the unglazed one. The maximum supply percentage can reach 69.4% and the temperature rise is approximately 20 °C. Finally, a parametric investigation is carried out on different functional buildings, and an optimal structure in Xi'an is given as a reference. The energy collection and transfer efficiency increase with the increase of air volume, but the energy saving rate decreases. The results indicate that this solar wall is ideal for buildings with low fresh air demand, such as single residences and small offices. It also has a considerable preheating effect on high fresh air demand ones.