dc.description.abstract | In this study, the numerical simulation has been performed in order to clear the effect of transverse magnetic field during crystal growth that compared the flow of melt, temperature distribution and velocity distribution in the melt between transverse magnetic field and no magnetic field, and also compared in different crystal pulling rate. The Lorentz force induced by transverse magnetic field strongly affected the melt flow. Melt flow was Three-dimensional, so there were two different flow patterns on plane along and crossing transverse magnetic field, separately. Melt flow went down to the bottom of crucible on the plane along magnetic field. By contrast, melt flow maintained with full vortex on the plane crossing magnetic field. A stronger spiral vortex motion is formed under the crystal-melt interface that makes the interface in transverse magnetic field was more uniform in no magnetic field. Heat transfer was influenced by these two different flow patterns in two directions. Thus, both temperature distribution and the highest temperature were different in two perpendicular directions. Temperature of crucible with transverse magnetic field is higher than that without magnetic field. So, not only the temperature gradient but also the temperature gradient on melt-crystal interface with transverse magnetic field was higher than that without magnetic field. Melt flow velocity with transverse magnetic field was lower than without magnetic field and there were different velocity distributions in transverse magnetic field and without magnetic field. With transverse magnetic field, most parts of melt flow were slow, but velocity increased near the triple point. At the melt-free surface, flow velocity with transverse magnetic field was strongly lower than that without magnetic field. This paper also discussed about melt flow patterns, temperature field, and velocity field using different crystal growth rates with transverse magnetic field and without magnetic field. With increasing crystal growth rate, the melt-crystal interface of transverse magnetic field was more convex toward crystal than one without magnetic field. Melt temperature field is similar to each other with different crystal growth rates, but the highest point decreased with increasing crystal growth rate. However, the temperature gradient on melt-crystal interface increased with increasing crystal growth rate. Melt velocity field was little affected by changing crystal growth rate, and velocity field was similar to each other, and so as near melt-free surface the velocity changed slightly.
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