Comparison of quasi-steady-state and unsteady-state formulations in a freeze dryer modeling

Abstract

An unsteady-state model is developed for primary and secondary stages of freeze drying process of skim milk. The results are compared with those obtained from a quasi-steady-state (QSS) formulation. The QSS formulation is not valid where the applied heat load is high. The applied heat load affects on the drying time the most compared to other parameters like chamber pressure and the radiation surface temperature. © 2014 Springer-Verlag Berlin Heidelberg.