A numerical study on the effect of vent/wall area ratio on Trombe wall thermal performance

Abstract

Trombe walls are the most widely applied passive systems that utilise solar energy for heating massive walls. Although studies have been undertaken in the fields of Trombe wall application and design, the research on the effect of the vent area and the number of vents on the performance of a Trombe wall remains limited. In this context, a parametric study investigating the effect of the vent-to-wall-area ratio on Trombe wall performance was conducted. A computational fluid dynamics model was employed for validation analysis. The results were verified by experimental measurements of temperature. At each step of the parametric study, the vent-to-wall-area ratio in the Trombe wall model was increased by 2% starting from the unvented case, and the results were simulated per ratio. In this study, temperature measurements of the glazing, thermal wall and space were employed as the evaluation criteria. The results of the parametric runs showed that a Trombe wall with eight separate air vents and an 8% vent-to-wall-area ratio provides the maximum heating performance. Furthermore, a monolithic vent configuration with an 18% vent-to-wall-area ratio performed slightly better compared with other configurations of monolithic air vents.

Türkiye’deki Trombe Duvarı Sistemine ait Sayısal Isı Akışı Analizi

“…There is also a relatively complex structure compared to traditional buildings, subjected to thermal optimization studies (Demirbilek et al, 2003) by taking into consideration of glazing, thermal wall thickness, window/wall ratio and insulation material selections all at once. Phase change materials have also been used lately in improving Trombe wall efficiency by several researchers (Xiong et al, 2022;Duan et al, 2021) On the other side, CFD programs are often used by researchers when dealing with temperature distribution, air flow/circulation and ventilation problems where density changes and buoyancy effect get involved (Jaber and Ajib, 2011; Kaya et al, 2021). In this manner, vent optimization related research studies have employed and taken advantage of CFD fluent environments.…”

“…In spite of a large number of research studies undertaken, yet only few referred how to adjust vent size and dimensions for obtaining optimum performance (Briga et al, 2014;Jaber and Ajib, 2011). A recent study (Kaya et al, 2021) has pointed out this research gap and investigated the effect of total vent/wall area ratio on TWs thermal performance by increasing this ratio by 2% starting from unvented case. The results showed that any TW configuration with 8% vent/wall ratio provides maximum heating performance.…”