Modeling and numerical solution of eggplant freezing during freeze-drying process

Taking the research object of eggplant spherical samples, the modeling and numerical solution to the pre-freezing process of fruits and vegetables were studied. The non-steady-state mathematical model of fruits and vegetables was established by means of energy balance. Based on the test process parameters, the problem for determining solution was given, which met the temperature changing of samples in liquid phase region and solid phase region during the freeze-drying process. Using numerical method of Euler receding difference scheme, the numerical solution to the freezing mathematical model was found, and the freezing time and the displacement law of freezing boundary were concluded. Test results showed that: the model could describe the freezing process of eggplant accurately, and the numerical solution was feasible. The research provided a means of modeling and solution to fruits and vegetables, and the theoretical basis for optimal control was proposed during the pre-freezing process.