Investigation of Paddy Drying in a Curvilinear Impinging Stream Drying System Using Computational Fluid Dynamics
DOI: 10.14416/j.ind.tech.2026.04.007
Keywords:
Impinging stream, Paddy; Moisture content, Drying, Volumetric evaporation rateAbstract
This research was to investigate the simulation of paddy drying in a curvilinear impinging stream drying system by computational fluid dynamics. In this study, a three-dimensional steady-state model was used to calculate the drying characteristics in a curvilinear impinging stream dryer. The gas and solid phase equations were solved using the Eulerian and Lagrangian methods, respectively. The model was used to simulate the effects of various parameters including inlet air velocity of 25 m/s, inlet drying air temperatures of 70, 90 and 110 ºC, paddy feed rate of 25, 35 and 56 kg/h on the paddy mean residence time, paddy mean moisture content and volumetric evaporation rate. Simulated results were compared with experimental data. The results showed that the model could predict the paddy mean residence time and paddy mean moisture content were close to the experimental results within ±6%. The simulated results revealed that the moisture reduction rate of the paddy depended both on the inlet drying air temperature and paddy feed rate. The maximum volumetric water evaporation rate was 62.72 kgwater/m3h when using inlet air velocity of 25 m/s, inlet drying air temperatures of 110 ºC and paddy feed rate of 56 kg/h. Based on the simulated results, the optimum paddy feed rate of this curvilinear impinging stream drying system was around 80 kg/h.
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