摘要
A theoretical investigation of fluid flow,heat transfer and solidification(solidification transfer phenomena,STP)was presented which coupled with direct-current(DC)magnetic fields in a high-speed strip-casting metal delivery system.The bidirectional interaction between the STP and DC magnetic fields was simplified as a unilateral one,and the fully coupled solidification transport equations were numerically solved by the finite volume method(FVM).While the magnetic field contours for a localized DC magnetic field were calculated by software ANSYS and then incorporated into a three-dimensional(3-D)steady model of the liquid cavity in the mold by means of indirect coupling.A new FVM-based direct-SIMPLE algorithm was adopted to solve the iterations of pressure-velocity(P-V).The braking effects of DC magnetic fields with various configurations were evaluated and compared with those without static magnetic field(SMF).The results show that 0.6 T magnetic field with combination configuration contributes to forming an isokinetic feeding of melt,the re-circulation zone is shifted towards the back wall of reservoir,and the velocity difference on the direction of height decreases from 0.1 m/s to 0.Furthermore,the thickness of solidified skull increases uniformly from 0.45 mm to 1.36 mm on the chilled substrate(belt)near the exit.
A theoretical investigation of fluid flow, heat transfer and solidification （solidification transfer phenomena, STP） was presented which coupled with direct-current （DC） magnetic fields in a high-speed strip-casting metal delivery system. The bidirectional interaction between the STP and DC magnetic fields was simplified as a unilateral one, and the fully coupled solidification transport equations were numerically solved by the finite volume method （FVM）. While the magnetic field contours for a localized DC magnetic field were calculated by software ANSYS and then incorporated into a three-dimensional （3-D） steady model of the liquid cavity in the mold by means of indirect coupling. A new FVM-based direct-SIMPLE algorithm was adopted to solve the iterations of pressure-velocity （P-V）. The braking effects of DC magnetic fields with various configurations were evaluated and compared with those without static magnetic field （SMF）. The results show that 0.6 T magnetic field with combination configuration contributes to forming an isokinetic feeding of melt, the re-circulation zone is shifted towards the back wall of reservoir, and the velocity difference on the direction of height decreases from 0.1 m/s to 0. Furthermore, the thickness of solidified skull increases uniformly from 0.45 mm to 1.36 mm on the chilled substrate （belt） near the exit.
基金
Projects(51071062,51271068,51274077)supported by the National Natural Science Foundation of China
Project(2011CB605504)supported by the National Basic Research Program(973 Program)of China
