CFD simulation of Laval nozzle for micro atmospheric water generator
                             CAI Shen1, LI Song jing1,2, WU Hai cheng1, YUAN Shuai1, ZHOU Li gen2, ZHANG Liang2
（1.School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China;2.Yangzhou Nier Hydraulic Technology Co. Ltd., Yangzhou 225811, China）


Abstract: Aiming at the problem of harvesting water efficiently from air, a micro atmospheric water generator based on hygroscopic material was studied. A Laval nozzle for micro atmospheric water generator was designed to improve efficiency. The relation between Laval nozzle structure and air flow in the generator was investigated by employing a CFD （Computational Fluid Dynamics） numerical simulation. The mass flow based on different diameter and height of nozzle “throat” was analyzed. The results indicate that utilization of Laval nozzle can keep pipe heat insulation, reducing the internal air density, and form the negative pressure area because of the air acceleration effect. Appropriate Laval nozzle can increase mass flow rate in the generator by 50%. The adjustment of Laval nozzle structure can keep the mass flow in the best range and increase work efficiency.
Key words: Laval nozzle; atmospheric water generator; CFD