Design and Thermodynamic Research on Microfluidic-Atmospheric Water Generator

A portable microfluidic device, composed by an absorbing and heating module, an energy module and a condensing module, was presented for generating fresh water from outdoor air. Based on the working principle of general atmospheric water generator, an attempt mathematic model was designed and established. The functional structure in the condensing module was microfluidic channel, which had compact size and good thermal conductivities. The dynamic characteristics of thermal-fluid coupled fields during phase changing processes (evaporation and condensation) were simulated respectively. COMSOL Multiphysics was used to study the heating-evaporation process and ANSYS ICEM CFD was used to simulate the condensation process. Vary characteristics of fluid field, temperature field and volume fraction distribution while water being generated were observed and then analyzed. Based on the findings of the analysis, a modified device was designed and fabricated. Simplified soft etching process was chosen to manufacture the micro channel in the condensing module. Several test experiments were recorded by thermal infrared imager to detect the temperature distribution during water generating process. The test results agreed well with the former simulation results, both of which would provide significant referential experience for commercial microfluidic-atmospheric water generator design in the future.