Thin layer modelling and thermal performance of active mode modified greenhouse solar dryers

Abstract

Open sun Crops drying is common in India even though a considerable time and dust accumulated. This is a serious issue. Workman ship and time reduction is needed to increase the productivity. Introduction of Green house solar dryer should be a right choice as against the conventional drying. The novel research focuses for retaining the nutritional values at higher level, very clean and with very less time for drying and supports the farmers at very affordable cost of drying. The four dryers are fabricated with two different roof materials and shapes. Each dryer bottom surface it is staked with three layers namely, black painted plywood, black PVC sheet of 3 mm thickness and stainless steel wire mesh tray. The results were noticed that moisture in the green peas is reduced from 76% to almost 9% in all dryers. The parabolic poly ethylene greenhouse solar dryer took 20 solar hr., whereas OSD took 32 solar hrs, in turns the saving of drying time is 37.5% compared to OSD. Different thin layer models were studied to fit with experimental data. Among all the thin layer models, Midilli and Kucuk model with PPEGHSD had shown a better agreement than the other models for the green peas. The performance and nutrition analysis have been carried out to ensure the quality of the dried products. It is observed that all the nutrition element values in the PPEGHSD are higher than the all other dryers and is suggested for the successful food grains drying.