Thin Layer Modeling and Solar Drying Characteristics of Forced Convective Hybrid Photovoltaic Thermal (PV-T) Solar Dryer Assisted with Evacuated Tube Collector for Drying of Untreated Potato Slices

Abstract

In the present work, a forced convective hybrid photovoltaic thermal (PV-T) solar dryer assisted with an evacuated tube collector (ETC) is set up to investigate the thin layer drying of potato slices. The drying experiment is compared with the traditional sun drying method without PV-T system under the meteorological conditions of Thanjavur, Tamilnadu. The initial moisture content of potato slices used for the study is 91% (wb). The drying experiment was carried out at different air temperature levels of 50, 55 and 60 °C. Nine numerical models are used to study the drying kinetics of untreated potato slices. Using IBM SPSS 23 statistical package, non-linear regression analysis was performed to estimate correlation coefficient (R2), reduced chi-square (χ2) and root mean square error (RMSE). The model developed by Midilli et al., is the most appropriate one to describe potato slices thin layer drying behavior in a hybrid dryer. The effective moisture diffusivity (Deff) determined using Fick’s second law of diffusion was found to vary from 2.12463×10-8 to 2.79233×10-8 m2/s. The activation energy (Ea) determined using the Arrhenius equation was found to be 16.4276 KJ/mol for drying of potato slices.

Keywords

• activation energy
• effective moisture diffusivity
• evacuated tube collector
• hybrid photovoltaic thermal solar dryer
• thin layer drying kinetics