Establishment and application of a simulation model for infrared radiation combined with hot air intermittent drying of jujube slices

Fresh jujube is prone to rotting and deterioration after harvesting; hence, effective methods to extend their storage time are needed. To date, limited work has been done on intermittent infrared combined hot air drying modeling. Therefore, this study aimed to investigate the temperature and moisture distribution of jujube slices subjected to intermittent drying and optimize the drying process. A 3-dimensional (3D) mathematical model for jujube tempered drying was developed to simulate heat and mass transfer using intermittent drying under nine different intermittent ratios. Simulated results were in good agreement with the experimental results measured using a temperature sensor probe and magnetic resonance imaging, The minimum value of R 2 was 0.953 and the maximum value of RMSE was 0.51. The tempering period efficiently reduced the duration that the material was exposed to high drying temperatures, while also optimizing the moisture distribution, the upper layer MC increased from 19.232 to 19.986 % d. b, and the lower layer MC decreased from 22.628 to 21.735 % d. b. during the first tempering period. By comparing the simulation results with the experimental data, we determined that reduced drying time and increased product quality was best achieved at the intermittent ratio of 40:40. Overall, this modeling approach can be used to optimize the intermittent drying process and reduce experimental costs. • We developed a 3-dimensional mathematical model for infrared radiation combined with hot air intermittent drying (IIRHAD) of jujube slices. • The simulation model acquired satisfactory results for temperature and moisture prediction. • The simulation model demonstrated that the tempering period efficiently reduced the length of time that the material was exposed to high drying temperatures, while also optimizing the moisture distribution. • IIRHAD with different intermittent ratios (IR) were simulated to compare and evaluate features.