Optimization of Hybrid Solar Drying of Okra by Using Response Surface Planes

Year 2025, Volume: 8 Issue: 6, 785 - 790, 15.11.2025

Hatice Dilaver , Kamil Fatih Dilaver

https://doi.org/10.47115/bsagriculture.1686701

Abstract

This study employs the Response Surface Methodology (RSM) with a Central Composite Design (CCD) to optimize the hybrid solar drying process. Sixteen experimental runs were conducted based on three key input variables, leading to the formulation of a second-order regression model that explains the effects of these parameters on drying duration and energy consumption. Using data analysis via Minitab software, the optimal conditions were identified to achieve a final product moisture content of 15% (wet basis) while minimizing drying time and energy usage. The results revealed that energy demand increases with greater slice thickness, drying temperature, and air velocity, whereas drying time rises with slice thickness but decreases with increasing temperature and airflow. High agreement was found between the predictive models and experimental observations, with R² values of 99.3% for drying time and 99.8% for energy consumption. The optimal drying conditions were 40 °C air temperature, 11.5 mm slice thickness, and 1.02 m/s air velocity.

Keywords

Solar drying , Optimization , Response surface methodology , Drying duration

Ethical Statement

Ethics committee approval was not required for this study because there was no study on animals or humans.

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