Multi-block patched grids in conjunction with a finite volume time domain (FVTD) algorithm are used to solve classic multi-body electromagnetic scattering problems. The governing equations of the Maxwell equations are cast into three-dimensional general curvilinear coordinates. The approach uses four-stage Runge-Kutta scheme for time integration and flux vector splitting based on eigen structure of flux Jacobian matrices for spatial discretization. Monotonic upstream shemes for conservation laws (MUSCL) scheme for interpolation is used for the dependent variable. The resolution for temporal discretization is second order and that for spatial discretization is third order. Numerical results for the radar cross section(RCS) of a classical configuration agree well with the analytical results. And the results for multi-body calculation agree well with that in references. It shows that the algorithm developed is able to simulate complex topology configuration (including multi-body) problems.

Based on the third-order ENN scheme, a fourth-or fifth-order WENN scheme is developed by using the weighted function, and then this scheme is applied to a shock-induced mixing flow. Numerical results show that the degree of mixing enhancement can be increased by the shock-induced technique, and that this WENN scheme exhibits a good resolution for the flow field.

By using the quasi-3D coupled current method presented, the influences of structure of cold crucible, power frequency, electricity property of charge(melt), coil(inductor)position and current on the electromagnetic field(EMF) and the levitation characteristics in the melting processes are analyzed. It is shown that in the melting process, power frequency and crucible structure are the decisive factors for the ability of penetrating magnetic flux into cold crucible. The magnetic flux density in cold crucible is reduced with the rising of power frequency, and this tendency becomes stronger when that is higher than 100 kHz. The segmented structure of cold crucible can reduce the induction eddy in itself effectively, and the higher the power frequency is, the better the result is. So, a cold crucible can be segmented into(16~20) sectors for higher frequency electromagnetic field(f>100 kHz),(8~12) sectors for high frequency one(10 kHz≤f≤100kHz), and(4~8) sectors for mid-high frequency one(f<10 kHz). It is also shown that the levitation force in melting charge is related to coil current as a parabolic function.