摘要
为优化电磁搅拌工艺,建立了电磁搅拌过程的电磁-热-流体耦合场数学模型,并用ANSYS软件进行了三维数值模拟。结果表明,电磁搅拌时坩埚内浆料中磁感应强度、速度场以及温度场均呈三维分布,浆料顶部中心区域的速度分布揭示了增强颗粒进入浆料的动力学条件,而浆料内的循环流以及坩埚壁附近的剪切流可使初生相、增强颗粒与流体之间产生摩擦、剪切和碰撞,为得到球状晶和实现增强颗粒的复合创造了条件。温度场计算结果表明,在制定搅拌工艺时,应根据合金的两相区大小和增强颗粒加入量等,使冷却速度和搅拌时间相匹配。电磁搅拌可使温度分布均匀,扩大等温区,有利于晶核的形成及按等轴晶方式长大,为得到半固态组织创造了条件.
In order to optimize electromagnetic stirring process,the electromagnetic-thermal-fluid coupling field mathematic model was established and the three-dimensional simulation was also done by using ANSYS software.The simulation results showed that the magnetic induction intensity,velocity and temperature field of the slurry showed three-dimensional distribution in the crucible.At top center area of slurry,the velocity distribution indicated the dynamic condition of reinforced particle entering slurry.The circulation flows in the slurry and the shear flows at crucible area made primary phase,reinforced particle and fluid rub,shear,impact mutually.That created the conditions to obtain spherical crystal and make reinforced composite.The temperature field calculation results indicated the stirring time and cooling rate must match each other,according to two phase interval and quantity of reinforced particles,when the stirring process was established.Electromagnetic stirring made temperature field distribute well and isothermal region expand.It did favor to crystal nucleus form and grow according to equiaxed grain mode and created conditions to obtain semi-solid slurry.
出处
《沈阳理工大学学报》
CAS
2011年第6期1-6,共6页
Journal of Shenyang Ligong University
关键词
电磁搅拌
电磁场
流场
温度场
数值模拟
electromagnetic stirring
electromagnetic field
fluid field
thermal field: numerical simulation
