Thermal modeling and drying kinetics of gooseberry drying inside north wall insulated greenhouse dryer

The north wall insulated greenhouse dryers with solar air heating collector are used for gooseberry drying under passive and active modes till stagnation in their moisture evaporation. Experiments are performed simultaneously for open sun, passive and active modes to validate thermal models and compare their drying kinetics. The predicted moisture evaporation rate, gooseberry surface and greenhouse room air temperatures show the fair agreement with the experimental observations within the root mean square of percentage deviation ranges from 4.58 to 16.39% and coefficient of correlation ranges from 0.96 to 1 under passive and active mode. For active mode, coefficient of correlation ranges from 0.94 to 0.99 and root mean square of percentage deviation ranges from 3.49 to 12.24%. The passive mode greenhouse dryer was found more effective than other dryers. Based on SSE, R-square, adjusted R-square and RMSE, Prakash and Kumar model was selected as best curve fitting technique for non-linear regression analysis for gooseberry drying under passive mode. The proposed thermal model will be useful tool for designing energy efficient greenhouse drying system for given mass and location. (C) 2017 Elsevier Ltd. All rights reserved.