Experimental and numerical study of performance enhancement in a direct solar dryer integrated with obstacles

[Display omitted] •Novel heat transfer enhancement approach in solar dryers.•Design importance to improve solar drying technology.•Comparative drying performance of direct solar dryer with and without obstacles.•Numerical and CFD analysis is key to assessing and comparing efficiency across solar drying configurations. Enhancing heat transfer is critical across diverse industrial and agricultural applications to optimize operational efficiency and reduce energy consumption by maximizing thermal energy exchange between systems and their surroundings. This study investigates heat transfer enhancement in a direct solar dryer through the strategic integration of obstacles, addressing a significant gap in existing literature that primarily focuses on redesigning drying chambers and enhancing solar air collectors without improving internal performance. The primary objective was to enhance heat transfer efficiency within the drying chamber, which is needed to accelerate the drying process of agricultural products. By strategically placing obstacles, turbulence in the airflow was induced to improve mixing and heat distribution. This approach was validated through experimental observations and Computational Fluid Dynamics (CFD) simulations using ANSYS Fluent. The results indicate that integrating obstacles significantly raised the maximum dryer temperature from 10 °C without obstacles to 14.1 °C with obstacles. Numerical findings demonstrate improved air distribution within the chamber, generating high-velocity zones near obstacles and enhancing overall air circulation. Furthermore, integrating obstacles reduced drying time by more than 4.5 h and achieved a maximum thermal efficiency of 69.39 %. Additionally, this enhancement contributed reducing CO2 emissions to 36.01 kg per year, underscoring the system’s environmental benefits.