A Numerical Study on Freeze Drying Characteristics of Cylindrical Products with and without Container
Chi Sung Song and Jin Hyun Nam
Freeze drying of cylindrical products with and without container was studied to make clear the effect of presence/absence of the container on freeze drying characteristics and drying time. For accurate numerical simulations, a multidimensional freeze drying analysis program was developed by the authors based on a finite volume method in a fixed grid system. The simulation results showed that the increase in the mass transfer surface area was favourable for both the reduction in the freeze drying time and also the reduction in the average product temperature in the frozen region. The primary direction of drying changed from axial direction (from top surface to bottom surface) to radial direction (from lateral surface to centreline) according to the diameter of the cylindrical products.