Abstract
Freezedrying is a preservation process, consisting of two main stages: during the primary drying water is removed by sublimation; during the secondary drying chemically bound water is removed by desorption. Two different models of secondary drying are built. The first one consists of coupled heat and mass balances equations, the second one uses a modified Richards equation. Using scale transformations derived from the PDEs and the BCs, the first model is nondimensionalized. The model is further simplified by asymptotic reduction. It is proven that the reduced model is equivalent to the model that uses the modified Richards equation if the partial pressure of air is negligible compared to that of water vapor in the vials and in the chamber of the freezedrier. This result shows that there is an opportunity for technology transfer, since solvers developed for modelling groundwater flows using Richards equations can also be used to model the economically important problem of freezedrying.
Original language  English 

Title of host publication  Advanced Computing in Industrial Mathematics 
Subtitle of host publication  Revised Selected Papers of the 10th Annual Meeting of the Bulgarian Section of SIAM December 2122, 2015, Sofia, Bulgaria 
Editors  Krassimir Georgiev, Michail Todorov, Ivan Georgiev 
Publisher  Springer Verlag 
Pages  231238 
Number of pages  8 
Volume  681 
ISBN (Electronic)  9783319495446 
ISBN (Print)  9783319495439 
DOIs  
Publication status  Published  7 Feb 2017 
Externally published  Yes 
Event  10th Annual Meeting of the Bulgarian Section of SIAM  Sofia, Bulgaria Duration: 21 Dec 2015 → 22 Dec 2015 Conference number: 10 http://www.math.bas.bg/IMIdocs/BGSIAM/bgsiam15_announcement.htm (Link to Conference Website) 
Publication series
Name  Studies in Computational Intelligence 

Publisher  Springer 
Volume  681 
ISSN (Print)  1860949X 
Conference
Conference  10th Annual Meeting of the Bulgarian Section of SIAM 

Abbreviated title  BGSIAM 2015 
Country  Bulgaria 
City  Sofia 
Period  21/12/15 → 22/12/15 
Internet address 
