Abstract: Combining the poor performance of water spout, the structural characteristics of the water nozzle of a drinking machine is analyzed and the structural characteristics that affect the atomization of water and drift of water are determined; The structure of the original water nozzle is optimized to improve the flow field performance of the water nozzle, which including the porous baffle for buffering incident stream and the gradual shrinkage structure of the front section of the outlet and the diversion structure of the outlet with the method of the steepest descending line theory. Based on the VOF method, the internal gas-liquid distribution and flow field distribution of the optimized water nozzle and the original water nozzle are compared and analyzed. The numerical analysis shows that the flow field of the optimized nozzle has been significantly improved, which can effectively improve the problem of atomization of water and drift of water. The high temperature resistant prototype of the optimized water nozzle is made for testing of the water withdrawal process of the drinking machine. The flow field performance of the optimized water nozzle has been significantly improved in the test.

Key words: Atomization of water, Drift of water, Porous baffle, Steepest descending line