A Review on the Use of Vortex Generators in Solar Air Heaters: Experimental Insights and Theoretical Models for Performance Improvement

Abstract

This review investigates the use of vortex generators (VGs) in solar air heaters (SAHs) to enhance thermal performance and efficiency. Vortex generators, as passive elements, disrupt airflow to promote turbulence, thereby improving heat transfer and mitigating inherent inefficiencies in traditional SAHs. The review consolidates experimental findings and theoretical models to evaluate the influence of various VG configurations, such as delta-winglets and perforated ribs, on convective heat transfer. Insights into the role of parameters like geometry, pitch ratio, and placement are provided, highlighting their effects on thermal and hydraulic performance. Computational Fluid Dynamics (CFD) simulations are emphasized as a pivotal tool in analyzing fluid dynamics and optimizing VG design. Challenges like balancing pressure drops, material degradation, and scalability are explored, alongside potential solutions through hybrid systems and advanced design methodologies. Future research directions are outlined to address economic viability and long-term reliability, emphasizing the integration of VGs into more adaptive and modular SAH systems. This study underscores the critical role of innovative VG technology in advancing solar heating solutions to meet sustainability goals.