冷热坩埚中电子枪加热金属熔池的数值分析

Numerical analysis of molten pool heated by electron gun

利用Navier Stokes方程在一定的边界条件下求解了电子枪加热长槽形冷、热坩埚中的二维熔池流场 ,获得了熔池流场的速度和温度分布 ,并且详细地对比研究了冷、热坩埚中金属熔池的蒸发量与电子枪功率、束宽以及坩埚尺寸的关系 .电子枪功率越高、束宽越小 (除非小于 0 5mm)、坩埚尺寸越大 ,则蒸发量越大 ,电子枪能量的有效利用率也越高 .当电子枪束宽较大时 ,热坩埚的蒸发量较大 ,而当束宽较小时 ,冷坩埚的蒸发量较大 .计算中对铁、铜、钆和铝等金属熔池进行了数值分析 ,获得了相似的结果 .

It is necessary to know the characteristics of the metal molten pool in many fields. The velocity and temperature distribution of the two-dimensional pool in both the cold and the hot crucibles heated by the electron gun are analyzed by the Navier-Stokes equation under the real boundary condition. The relations between the evaporation rate and the power of the electron gun, the width of the electron beam I the volume of the crucible are studied in detail for the cold and hot crucibles. In general, the evaporation rate increases with the power of the electron gun increasing, the width of the electron beam decreasing ( except the width less than 0.5mm) and the volume of the crucible increasing, so the effective power use ratio of the electron gun increases. The evaporation rate of the hot crucible is higher if the electron beam is wider, otherwise the evaporation rate of the cold crucible is higher. The results are similar for iron, copper, gadolinium, aluminium and so on.