Numerical Optimization of Operating Parameters in a Photovoltaic Drying System

Abstract

In this study, the effects of the evaporator design on the thermal and fluid performance of photovoltaic-assisted solar drying systems were investigated using numerical methods. To optimize the temperature and mass flow rate of the air supplied to the drying system, Computational Fluid Dynamics (CFD) analyses were performed on evaporator models with different channel heights (3, 4, and 5 cm) under three different mass flow rate conditions (0.025, 0.050, and 0.075 kg/s). The obtained temperature contours and streamline patterns revealed that, particularly at a channel height of 3 cm and mass flow rate of 0.075 kg/s, the airflow made more effective contact with the surface, maximizing heat transfer. In contrast, for the 4 cm and 5 cm channels, the airflow moved away from the surface, leading to a reduced cooling performance and increased production costs. Considering the average outlet temperature and velocity values, the best performance was achieved with a 3 cm channel height – 0.075 kg/s mass flow rate configuration. Therefore, to enhance the efficiency of solar-powered drying systems, it is recommended to design an evaporator with a 3 cm channel height and operate it under high flow conditions. This study provides a valuable technical reference for engineers and researchers for the design of PV-based drying systems.

Keywords

• evaporator
• drying system
• efficiency
• thermal-fluid analysis
• CFD

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