| The physical fields in RH vacuum refining process,which will be used to refine liquid Al alloys,including effects of Ar flow,vacuum degree on the flow behaviors and efficiency of the impurity removal were worked out by numerical and physical simulation in this paper.The main results obtained as followings:A water model device with a 1:1 ratio to the prototype was established by the similar conditions.The water model experiment of argon and water two-phase flow was carried out.The influence of different parameters on the liquid-phase circulation flow was discussed.The simulation results of water model showed that the circling flow way is the liquid alloy flowed along up piper raised into vacuum chamber,into the bottom of the liquid alloy box along down pipe,then flowed in two directions along the bottom,finally raised along up pipe,which formed two circling flows.The number of the Ar bubbles rising from up pipe increased with increase in flow quantity of Ar.The flow model of Ar and the liquid is similar both in numerical simulation and water model experiments.The larger the Ar flow,the lower the vacuum degree,the shorter the time for uniformly mixing.The larger the circling flow,the shorter the time for uniformly mixing.The turbulent flow energy of the liquid is highest in up pipe and vacuum chamber and that is lowest below the up pipe.Increase in flow rate of the liquid will increased the turbulent flow energy of liquid Al,so that the circling flow in RH vacuum refining device will increased too.The content of Ar in the center of up pipe,flow rate of all liquid Al and circling flow will increased with increase in vacuum degree.The size of Ar bubbles has little effect on the gas content of liquid Al in up pipe and flow rate of all liquid.Increase in Ar flow rate,decreasing vacuum degree and size of Ar bubbles will help to increase in the impurity removal efficiency.Increase in flow rate of Ar intensified the impurity removal efficiency of RH vacuum refining device significantly. |
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