The coupled heat and moisture transfer in a counter flow hollow fiber membrane tube bank used for liquid desiccant regeneration are investigated. Two fibers

the solution stream inside the fibers

and the air stream surrounding the fibers are selected as the calculating domain. The partial differential equations governing the fluid flow and heat mass transports are established and solved by a controlled volume method and a body-fitted transform technology. The friction factor

Nusselt and Sherwood numbers in the unit cells during the desiccant regeneration process are obtained and analyzed. These fundamental data for the uniform temperature and heat flux boundary conditions are compared. The features of the heat and moisture transports for the solution regeneration are disclosed.