Performance of a bi-layer solar steam generation system working at a high-temperature of top surface
. School of Electrical and Power Engineering, China University of Mining and Technology, Xuzhou 221116, China; Center for Phononics and Thermal Energy Science, China-EU Joint Laboratory for Nanophononics, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China.. School of Electrical and Power Engineering, China University of Mining and Technology, Xuzhou 221116, China; Department of Mechanical Engineering, University of Colorado, Boulder, CO 80309-0427, USA
Many efforts have been focused on enhancing the vapor generation in bi-layer solar steam generation systems for obtaining as much pure water as possible. However, the methods to enhance the vapor temperature is seldom studied although the high-temperature vapor has a wide use in medical sterilization and electricity generation. In this work, to probe the high-temperature vapor system, an improved macroscopic heat and mass transfer model was proposed. Then, using the finite element method to solve the model, the influences of some main factors on the evaporation efficiency and vapor temperature were discussed, including effects of the vapor transport conditions and the heat dissipation conditions. The results show that the high-temperature vapor could not be obtained by enhancing the heat-insulating property of the bi-layer systems but by applying the optimal porosity and proper absorbers. This paper is expected to provide some information for designing a bi-layered system to produce high-temperature vapor.