Non-Isothermal, Flat-Plate Liquid-Desiccant Regenerators: A Numerical Study

Solar energy can play a significant role in increasing the environmental sustainability of air-conditioning systems and a number of thermally-driven solar air-conditioning technologies are available. Among these technologies, liquid-desiccant systems have the potential to operate efficiently at lower regeneration temperatures, allowing for better use of flat plate collectors. In these systems, air to be conditioned is dehumidified through direct contact with a desiccant solution. This solution is then heated at the regenerator and water is evaporated into a scavenging air stream. This paper presents an analysis of the heat and mass transfer in a parallel-plate internally-heated liquid-desiccant regenerator. Using a finite-difference technique, a numerical analysis was performed to solve the species and energy equations. The influence of regenerator hot water parameters (temperature and mass flow), and solar collector efficiency on regeneration capacity and specific energy consumption was evaluated.