摘要
建立了在圆坯二冷区脉冲磁致振荡条件下电磁场-流场-温度场耦合数学模型.利用ANSYS有限元软件,研究了在脉冲磁致振荡凝固细晶(pulse magneto oscillation,PMO)作用下铸坯内部磁感应强度、电磁力以及焦耳热的分布,并且通过耦合电磁力与焦耳热得到了相应流场及温度场的变化规律.研究表明,当铸坯中施加脉冲磁致振荡作用时在电磁力的驱动下,铸坯内部靠近线圈位置将形成上下2个回流区,这种形式的流动能够降低铸坯的中心温度,使得铸坯内部的温度场分布更均匀,有助于晶粒细化.
A mathematical model that couples electromagnetic field, flow field and temperature field is established to study round billet secondary cooling zone under pulse magnetooscillation pulse magneto oscillation(PMO) using the finite element analysis software ANSYS. Billet internal magnetic flux density, electromagnetic force and Joule heat distribution are analyzed. Distribution of the flow field and temperature field are obtained according to the coupling electromagnetic force and Joule heat. The results show that an upper and lower recirculation zone is formed since a driving electromagnetic force is generated by pulse magneto-oscillation. The flow can reduce billet center temperature. As a result,the internal temperature distribution becomes more uniform, which is beneficial to grain refinement.
引文
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