A state-to-state model is used to simulate thermochemical nonequilibrium nozzle flow of N₂/N mixture. Quasi-onedimensional nozzle flow at reservoir temperature from 3 000 K to 8 000 K and pressure from 1 atm to 10 atm is simulated numerically to obtain flow properties,especially detail vibrational population distribution. Evolution of macro- and micro-properties of nonequilbrium flow during expanding is analyzed. Rationality of two-temperature or multi-temperature approach is investigated for recombination dominating flows.

Three dimensional unsteady natural convective heat transfer in an inclined cubic enclosure with porous medium is studied numerically. The right side wall (X=1) of the enclosure is kept at a constant temperature of T_o, Temperature of the opposite vertical wall (X=0) varies by sine law with a mean value of T_o. Other walls are kept adiabatic. A Brinkman-extended Darcy model is used to describe flow through porous medium in the enclosure and the equations are solved with SIMPLE algorithm. Inclination angle α1 rotating around Y coordinate varies between 0å and 90°. Inclination angle α2 rotating around X coordinate varies between 0° and 45°. Dimensionless temperature oscillation frequency f ranges from 5° to 90π. Effects of inclination angles and temperature oscillation frequency on heat transfer are studied in detail. It shows that the maximal heat transfer is achieved at an inclined angles α1=46°, α2=45° and a temperature oscillating frequency f=45π.

We study heat transfer and fluid flow in a complex enclosure fiLled with porous media, with SIMPLEC (Semi-Implicit Method for Pressure Linked Equations Consistent) algorithm in curvilinear coordinates. The upper and lower walls of the enclosure are horizontal and adiabatic. The vertical wall forms cosine curve and is kept at a constant temperature. Governing equations are discretized with a finite-volume method on body-fitted coLlocated grids. Brinkman-extended-Darey model and local thermal non-equilibrium model are used to solve momentum and energy equations. Effects of parameters, such as Rayleigh numbers, Darey numbers and porosity, on heat transfer and fluid flow are studied. It is shown that Rayleigh numbers and Darey numbers have significant effect while porosity is negligible. There exists an optimal aspect ratio to make the heat transfer rate maximum.

Unsteady natural convection heat transfer of incompressible fluid in an inclined cavity filled with saturated porous medium is studied numerically.The temperature of the cold sidewall maintains constant and the temperature of the opposite sidewall varies sinusoidally with time.The Brinkman-extended Darcy model and SIMPLER algorithm are adopted.Comprehensive numerical solutions are acquired at a fixed Prandtl number Pr=1 and a Rayleigh number Ra=10⁶.The inclination angle of the enclosure α varies from 0° to 90°.The effects of α and dimensionless oscillation frequency f on the natural convection are analyzed.The maximum heat transfer is reached at f=60π and α=43°.

Periodically fully developed convective heat transfer characteristics in a two-dimensional wavy channel are investigated numerically with a constant wall temperature.The calculations are performed with Pr=0.7,Re=20~500 on non-orthogonal non-staggered grids generated by an elliptic equation system.A semi-implicit method for pressure linked equations revised (SIMPLER) algorithm in curvilinear body-fitted coordinates is employed.Effects of Reynolds number and geometric parameters,such as aspect ratio φ and shape ratio γ,on heat transfer and friction factor are studied.It shows that no recirculation region occurs through the whole channel at low Reynolds numbers,small aspect ratio or small shape ratio.With the increase of Reynolds number,aspect ratio or shape ratio,heat transfer is enhanced due to flow recirculation.Corresponding friction factor increases simultaneously.

A fully developed convective heat transfer inside a two-dimensional periodically wavy channel is investigated numerically with pulsating flows under a constant wall temperature. It is based on the SIMPLER(Semi-Implicit Method for Pressure Linked Equations Revised) algorithm in curvilinear body-fitted coordinates.Calculations are performed with Pr=0.7,Re=5~500 on a non-orthogonal non-staggered grid generated by elliptic equations. The effects of pulsatile parameters,such as pulsatile amplitude and frequency on heat transfer and flow friction,are studied.It shows that the vortice sweeping,diminishing and growing up due to pulsating flows enhance fluid pulsating and mixing,and lead to the enhancement of heat transfer.The intensity of heat transfer increases with the increase of Reynolds numbers and amplitudes and is independent of pulsating frequencies.The instantaneous flow resistance and Nusselts numbers present periodical cosine and sine variations, respectively.

A concrete algorithm of selecting delay time in the state space reconstruction in the mutual information method is introduced. A simple and practical program algorithm based on a reticulate layer is established. An analysis on calculated result shows that the mutual information needs to be computed to a certain reticulate layer in selecting delay time. Therefore, the algorithm is simplified significantly. The Lyapunov exponents calculation of attractors(Rossler and Lorenz) verifies the validity of this algorithm.

The spin reorientation of magnetic thin film on a simple cubic lattice is simulated by employing Monte Carlo method.The influence of the magnetic anisotropy and the long-range dipolar interaction on the spin configurations of the system is also studied in detail.Meanwhile,the phase diagrams and the distributions of spin configuration,magnetization,specific heat of the systems are obtained.The results show that in a range of parameters,a transition from out-of-plane to in-plane ordering with the increase of the temperature is possible.

A simple non-variational configuration-interaction theory is presented for the divalent atomic system with two electrons outside a closed shell core, such as an alkaline earth atom and its corresponding isoelectronic sequence. The theory is used for exact solution of the multiconfiguration state wave function and its corresponding energy eigenvalue in the system, and for quantitative analysis of configuration interaction which reflects the exchange and correlative interaction between electron-electron. Discussion focuses on the use of a nearly complete finite basis set construeted from B-spline which is capable of taking into account effectively the continum contribution from positive-energy one-electron orbitals confined in a finite volume. Numerical example is for Be atom of the divalent atomic system and the obtained result conforms excellently with experiment.