Numerical investigation of membrane based heat exchanger with partially blocked channels

Abstract

Contrary to the traditional approach assuming the same parallel plate membrane based heat exchanger, a new proposition of exchanger design is investigated in this paper. The channels of membrane based heat exchanger are partially blocked by insertion of metal blocks. In order to evaluate their impacts on the heat and mass transfer distributions, a two-dimensional model including the momentum, heat and mass transport equations is solved by CFD code. Significant parameters such as obstacles number and form ratio are mentioned. The results show that the including of obstacles enhances the heat and mass transfer rates between the fresh and exhaust air channels. A low obstacles number leads to a large (small) air temperature and specific humidity ratio values in the exhaust (fresh) air channel. In addition, obstacle form ratio has a strong effect on the temperature and humidity distributions when it becomes higher. Also, this investigation takes into account the effect of membrane proprieties and flow arrangements which also have a strong effect on the heat and mass transfer rates.