No abstract

The quality of dried products mainly depends on temperature and moisture content changes during the drying process, as they govern the quality determining reactions that take place during dehydration. The temperature and moisture fields developing in the drying material during drying can be determined by solving the governing differential equations. They describe the heat and mass transport in the material and on its surface. Therefor a lumped parameter model of the drying material was established, using discretization and calculation methods known from aerospace engineering. The paper describes these methods as well as the simulation results for the drying process. It provides information on the dependency of heat and mass transport coefficients on local temperature and moisture content. Finally, the results are compared to experimental results obtained in a previous study.

The quality of dried products mainly depends on temperature and moisture content changes during the drying process, as they govern the quality determining reactions taking place during the dehydration. For optimizing the quality of the drying process it is valuable to predict moisture content and temperature of the drying material during the drying process. Heat and mass transport in the material and on its surface can be described by partial differential equations. This paper describes a mathematical technique originally used in aerospace engineering which allows for solving the partial differential equations numerically. The lumped parameter model of the drying material enables to predict the influence of external process parameters on the drying characteristics of the product and its temperature.