Investigation of The Thermocapillary Flow in A Liquid Bridge subject to A Non-uniform Rotating Magnetic Field
The effect of an external non-uniform rotating magnetic field (RMF) on the thermocapillary flow in a liquid bridge under microgravity is studied numerically. The thermocapillary flow subject to a non-uniform RMF (7mT, 25Hz) is investigated over a range of Marangoni numbers (15-40). The results indicate that, in comparison with the thermocapillary flow without the magnetic field, the maximum tangential velocity is greatly enhanced and the maximum axial velocity is reduced significantly due to the effect of the non-uniform RMF. As a consequence, the thermocapillary flow remains steady and approximately axisymmetric under the effect of the non-uniform RMF. These results demonstrate that a non-uniform RMF can be used as an effective method to control the thermocapillary flow.
Magnetic field design for floating zone crystal growth
The magnetic fields produced by electrical coils are designed for P-doped Si crystal growth in a floating full zone in microgravity environment. The fields are designed specially to reduce the how near the free surface and then in the melt zone by adjusting the coil positions near the melt zone. The effects of the designed magnetic fields on reducing the Row velocity and the non-uniformity of the concentration distribution in the melt zone are better than those of the case of a uniform longitudinal magnetic field, obtained by numerical simulation. It is expected to improve the radial macro-segregation and reduce the convection in the crystal growth at the same time by using the designed magnetic field.
Investigations of dielectric gratings using electrodynamic models based on volume integral equations
Eigenmodes of planar and cylindrical dielectric gratings (DGs) and electromagnetic wave scattering from multiplayer DGs are investigated. The DG characteristics are calculated using numerical-analytical solution of integral equations (IEs).