Numerical Study On The Influence Of Vacuum Condition In Liquid Evaporation

In the process of Atomic Vapor Laser Isotope Separation,metal vapor is obtained by metal atomization in vacuum environment,and the subsequent laser excitation separation isotope process is completed,but the vacuum acquisition in practical engineering depends on the gas pump.On the one hand,the complete vacuum can not be achieved.On the other hand,the vacuum process energy consumption is very large.Therefore,it is of practical significance for engineering application to explore the distribution characteristics of metal atomic vapor obtained from metal evaporation under different vacuum conditions.In this paper,the two-dimensional planar metal evaporation process is simulated by DSMC method,the distribution characteristics of metal atoms vapor under different background gas conditions are compared,and the influence law of the same background gas on the evaporation process under different evaporation source conditions is investigated.The metal liquid evaporation process with absolute vacuum and background gas pressure of 0.01,0.1 and 1 Pa respectively is simulated,and the calculation results show that the influence of different background gas pressure on the near-liquid surface region is very limited.When the pressure is strong at 0.01 Pa,the background gas has a great influence on the vapor velocity of the metal atom,which significantly slows down the upward velocity component of the metal atom vapor,which will affect the excitation and extraction process of the metal atom.Numerical simulation of metal evaporation process under different parameters under the condition of 0.1 Pa background gas pressure shows that when there is a background gas,the vapor density associated with the evaporation rate of metal atoms is the main factor affecting the distribution of vapor parameters of metal atoms.The research in this paper shows that the influence of background gas pressure on the evaporation process of metal atoms is emphasized.