Simulation and analysis of drying process for recirculating grain dryer

The theory of thin-layer drying equations was used to set up a drying model which could simulate recirculating grain dryer. The model could be used to calculate the data of drying time, energy consumption, tempering coefficient, as well as the changes of grain moisture, temperature and humidity of exhaust air in drying process. By experimental validation, the model simulation conformed to the experimental results, and the model could be used to analyze the same kind of dryer’s working condition, and provide effective technical means for research and development as well as the improvement of the dryers. According to the model calculation, selecting appropriate temperature and mass flow rate of air can balance drying time and energy consumption, and the operation that could save energy and improve the grain quality was to keep low drying temperature at the initial stage of drying and gradually increase it. Proper increase in drying section cubage will significantly reduce drying time and energy consumption.