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Drying model for grains is still often adopted in most current numerical simulation for fruits and vegetables during drying, leading to low simulation accuracy, for the shrinkage effect was not considered in physical model and heat and mass transfer. In order to calculate the shrinkage model during hot-air drying and simulate the distribution of internal temperature and humidity field with and without shrinkage, white radish with uniform structure and visible shrinkage during drying was chosen as a representative material. The results of the drying experiment demonstrated that the sample length had a significant impact on the characteristics of shrinkage, and the isotropic rate of drying shrinkage was the best at a sample length-to-radius ratio of 10, at which point the Hatamipour model was most appropriate to explain the shrinkage law of white radish by hot-air drying. And then, the heat mass transfer of white radish during hot-air drying was investigated based on the coupled shrinkage equation and heat and mass transfer equations by moving mesh method. The numerical simulation results showed that the migration path of moisture inside the material became shorter after shrinkage, and the faster removal rate led to a significant reduction of both internal and external moisture content at each time point, as well as a reduction in the moisture gradient at the superficial layer of material. Compared with the model not considering shrinkage, the moisture evaporation in the early and middle stages of drying was larger, while the moisture content in the later stage was smaller, so that more heat would be consumed for moisture evaporation in the early and middle stages and the latent heat dissipation for evaporation in the later stage was reduced. The above phenomenon led to a rapid rise in material temperature to 30℃ and then slowly raised to an equilibrium temperature of 60℃, which was closer to the experimental value. Specifically, the deviations of simulation results for internal and external moisture and temperature of the material after combining the shrinkage equations were reduced from 17%~8% and 12~2℃ to 14%~3% and 3~2℃, respectively. Therefore, the numerical simulations based on moving mesh can effectively interpret the effect of shrinkage on the physical model of materials and the heat and mass transfer law, thus providing a higher computational accuracy and a reliable model for the analysis of the heat mass transfer during hot air drying.