Applicability of numerical prediction method of dynamic derivatives is studied with forced oscillation method and free oscillation method on the airframe/propulsion integrative vehicle with and without fairing. Effect of parameters on dynamic derivative prediction in forced oscillation method such as time step and oscillation frequency is analyzed in detail. It shows that forced oscillation method is well applied in dynamic derivative prediction of integrative vehicle with internal and external flow, while parameters select of time step, computational time and oscillation frequency are quite different from external-flow-only vehicle. Dynamic derivatives by free oscillation method are in agreement with results with forced oscillation method on external-flow-only vehicle. There is a difference about 50% on integrative vehicle with internal and external flow. Origin and mechanism of differences in two methods need to be deeply studied.

We adopt lattice Boltzmann method to investigate double diffusive natural convection around a heated cylinder in an enclosure with Soret and Dufour effects. The inner heated cylinder is located at center of a square enclosure and four surrounding walls are assumed with low temperature and concentration. In the model, distributions of velocity, temperature and concentration are solved with three independent LBGK equations which are combined into a coupled equation through Boussinesq approximation. Influences of Soret number and Dufour number on double diffusive natural convection are analyzed. Streamlines, isotherms, isoconcentrations, average Nusselt and Sherwood numbers around heated cylinder in enclosure are presented. It shows that Soret and Dufour effects have significant influence on double diffusive natural convection.

It is shown that various closed circuits formed by line-shaped metallic particles in composite induce great permeability. Effect of temperature on magnetic response is weak. Based upon effective medium theory,electric and magnetic response of composites containing line-shaped tungsten particles are addressed. Microwave absorbing composites are designed and optimized, which may be applied in high temperature circumstances.

Lattice Boltzmann method is adopted to investigate mixed convection in an enclosure filled with porous medium.A heated cylinder (D/L=0.4) is located at center of the enclosure with high temperature.Inlet flow with low temperature is located at lower-left wall of the enclosure and exit is at upper-left wall.Other walls are assumed adiabatic.Influences of Richardson number Ri and Darcy number Da on average Nusselt number Nu around heated cylinder are investigated while Prandtl and Grashof numbers are kept at 0.71 and 1.4×10⁴, respectively.It indicates that Nu decreases with increasing Ri.Influence of Richardson number on Nu is significant as Darcy number is great.At 10^-5≤Da≤10^-2, Nu increases with increasing Darcy number as forced convection dominates flow (Ri≤0.1).As natural convection dominates flow (Ri=10), Nu is not sensitive to Darcy number.

Lattice Boltzmann method is adopted to numerically analyze nonlinear characteristics of double diffusive mixed convection in an enclosure. A heated cylinder is located at center of the enclosure. Fluid flows from an inlet at lower-left wall of enclosure and an outlet is at upper-right,upper-middle and upper-left wall respectively. Simulation results indicate that there are steady stationary solution,periodic and aperiodic oscillatory solutions in double diffusive mixed convection at different parameters. Phase path of velocity of monitoring point finally reaches a point,a closed loop and irregular curves,respectively.

A semi-discrete central-upwind scheme for multi-class Lighthill-Whitham-Richards (LWR) traffic flow model is presented. It combines improved fifth-order weighted essentially non-oscillatory (WENO) reconstruction called WENO-Z with semi-discrete central-upwind numerical flux. WENO-Z reconstruction improves accuracy of solution with non-oscillatory property. Time integration is carried out with strong stability preserving Runge-Kutta method. Numerical results demonstrate the scheme is efficient.

A radial symmetrical model of radon transport in vicinity of an underground tunnel is developed with continuum mechanics theory.Distribution of radon concentration in the vicinity of tunnel is analyzed under the assumption that only diffusion and permeation are considered.Analytic solutions are obtained.A rock mass range affecting the radon concentration in the tunnel is defined as effective transport distance.Effective transport distance as functions of effective porosity and velocity are given.Expressions of radon exhalation rate on tunnel wall are shown.

A Langevin equation of fluctuating velocity of fluid ‘seen’ by particle is simplified in Minier's model.Autocorrelation of turbulence fluctuating velocity is obtained,which has non-isotropic property.Corresponding PDF model of particle is obtained and a simplified form is used to predict turbulent particle dispersion in grid-generating turbulence flow.PDF model is solved analytically and solutions are compared with experimental results of Wells and Stock.

In a model for interaction between one atmosphere uniform glow discharge plasma (OAUGDP)and air proposed by Shyy,electric field and electric forces acting on air as body force are obtained.The electric field is calculated with electric potential equation. The influence of OAUGDP on flows around a NACA0015 airfoil at low speed is investigated by solving N-S equation with a body force term.Plasma located upstream of the separation point damps the flow separation around the airfoil efficiently,while plasma located downstream of the separation point has little effect on the flow.It agrees with experimental observations. Effect of plasma on aerodynamics of airfoil and pressure distribution on airfoil surface are investigated.

Electronic structures of possible F-type color centers in PbMoO₄ crystals are studied within the framework of a fully relativistic selfconsistent Dirac-Slater theory with a numerically discrete variational (DV-Xα) method. The results show that:F and F⁺ centers result in donor energy levels in forbidden band; optical transition energies are 2.141 eV and 2.186 eV, corresponding to 518 nm and 567 nm absorption, respectivly. The 580 nm absorption band after photo-chromic effect results from F-type color centers in PbMoO₄.

A fifth-order semi-discrete central-upwind scheme for hyperbolic conservation laws is proposed. In one dimension, the scheme is based on a fifth-order central weighted essentially non-oscillatory(WENO) reconstruction:In two dimensions, the reconstruction is generalized by a dimension-by-dimension approach. A Runge-Kutta method is employed in time integration. The method requires neither Riemann solvers nor characteristic decomposition and therefore enjoys main advantage of the central schemes. The present scheme is verified by one and two dimensional Euler equations of gas dynamics and shows high resolution and high accuracy.

With a high-order weighted compact nonlinear scheme(WCNS) for space discretization,several different implicit methods,including LU-SGS,Gauss-Seidel point-relaxation,line-relaxation and GMRES(generalized minimal residual),are compared in the simulation of hypersonic viscous flows.Both point and line relaxations with analytical Jacobian matrix converge faster than those of LU-SGS.GMRES obtains a faster convergence rate combined with line relaxation.

For hyperbolic conservation laws, a third-order semi-discrete central-upwind scheme with less numerical dissipation is presented. The scheme is based on a third-order non-oscillatory reconstruction proposed by Liu and Tadmor. The local speed of wave propagation is also considered. An optimal third-order strong stability preserving(SSP) Runge-Kutta method is used for time integration. The resulting scheme is free of Riemann solvers and hence no characteristic decomposition is involved, so that it enjoys the advantages of central schemes. The present scheme is tested on a variety of numerical experiments in one dimension. To illustrate the improvement of the method, the results are compared with that of the original third-order semi-discrete central-upwind scheme. The numercial results demonstrate that the presented method reduce the numerical dissipation of the semi-discrete central-upwind scheme further and improve resolution of contact waves.

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.

The LSQ coupled states of l-shell are constructed by (U,D)L-LSQ scheme, where U(D) is the total orbital angular momentum of spin up(down) electrons, the LS and Q are the total orbital angular momentum, spin and quasispin respectively, the (U,D) L-LSQ is unitary transformation. The scalar operators which commute with the total orbital angular momentum, spin and quasispin operators, are constructed from 4 creation-annihilation operators, and the LSQ coupled states are further or complete classified by its eigenvalues. The complete classifications of coupled states for f- and g-shell are obtained, the primary results of complete classifications of coupled states for g-shell are listed.

By using the formalism ofsecond quantization and irreducible tensor,quasispin angular momentum scalaroperator Z(K),where K=2,…,2j,is constructed from 4 creation-annihilation operators.Theeigenvalues of Z(K) have special ability for classification of coupled states,by angular momentum J and quasispin Q the complete classification can be done only for j≤7/2,but by eigenvalues of Z(K)the complete classification have be donefor j≤15/2.The methods for calculating the eigenvalues of Z(K)are discussed,and the complete classifications for j≤15/2 are presented.

Four numerical methods for calculating coefficients of fractional parentage(CFP) of nucleons are compared,and the results show that the method of complete space by neutron-proton couplied is much better than that of over complete space,the method of factorization by group chains is much better than that of non factorization,and there are great differences of calculating amonut between different methods.

Visualization In Scientific Computing (VISC) is a rapidly developing application of computer graphics. This paper introduces a Visualization System In Quantum Mechanics-VISQUM, and discusses some methods and techniques used in this system.

According to the group chain[SO(5)⊃U(1)_DⓧSU(2)_T]ⓧ[Sp(2j+1)⊃O(3)],the coupling states of j-shell nucleons are classified by D=(n-2 j-1)/2,isospin T,angular momentum J and generalized quasispin[s,t],where s is generalized siniority and t is reduced isospin;the multiplicities classified are products of SO(5)⊃U(1)_DⓧSU(2)_T and Sp(2j+1)⊃O(3) group reduction multiplicities.The explicit formulas for the two group reduction multiplicities are presented,and some results calculated are listed.

A bisection method is presented for solving the eigenvalue problem of symmetric band matrices.This method is especially suitable for the case where only a few eigenpairs are needed. Further more,a modified strategy is also presented.The main idea is that firstly using the bisection for some steps to obtain an approximate eigenvalue,then Rayleigh Quotient Iteration is applied to extract the eigenvalue to a predifined accuracy.