型腔充填过程中气液两相流计算及三维自由表面的确定

针对液体充填型腔过程的特点，在固定计算域中数值模拟型腔充填过程中气液不相混两相流流场。采用了体积守恒形式的连续性方程，以防止由于气液两相密度差大而引起的数值求解中的不收敛现象。将PHOENICS软件的流场计算与守恒标量求解大变形自由表面的方法相结合，在固定计算域中完成了数值模拟三维液态充填型腔的过程。针对两种情况下的计算结果表明，本文提出的方法可用于高速充填过程和复杂型腔充填过程的数值模拟。

NUMERICAL CALCULATION OF GAS-LIQUID TWO-PHASE FLUID FLOW AND DETERMINATION OF FREE-SURFACE FOR MOLD FILLING PROCESS

According to the features of mold filling, the velocity field of gas liquid two phase flow was calculated in the fixed computational domain without mixed fluid. The continuum equation with conserved volume type was used to avoid divergence because of the big difference in density between gas and liquid. The conserved scalar equation was used to describe the free surface during the mold filling process, and the free surface was tracked by solving the conserved scalar equation under the condition of the given velocity field by PHOENICS code. Two cases were simulated with the method developed in the present paper, and the results showed that the method developed here can be easily used for the high speed filling process and 3 dimensional shaped cavity.