Construction and Performance Analysis of an Indirect Solar Dryer Integrated with Solar Air Heater

The use of conventional sources of energy for drying agricultural product is an expensive process in developing countries. Therefore, an appropriate technology for drying of agricultural produce has been developed and its performance for the drying of tomatoes was evaluated. An indirect type natural convection solar dryer was developed. The aim of this study is to evaluate dryer performance under natural and forced convection modes of drying. In natural and forced convection, air mass flow rates of 0.00653 kg/s and 0.019 kg/s respectively were obtained. Hot air reached an average drying temperature of 45 degrees C in natural convection and 40 degrees C in forced convection. The results obtained from natural and forced convection modes of drying were also compared with open sun drying. The colour, flavour and time required for drying is favorable in solar drying as compared to sun drying. (C) 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Noorul Islam Centre for Higher Education