We solve Navier-Stokes equation with chemical source term, focusing on effect of three oxygen-hydrogen chemical reaction mechanisms on ignition, combustion efficiency and area compression ratio of reactive shock bubble interaction(RSBI). These chemical reaction mechanisms are Evans-Schexnayder(ES) model, Jachimowski(J) model, Ó Conaire(Ó) model, respectively. Results simulated with ES model show that subjected to shock wave,bubble has the largest ignition delay; the lowest balanced temperature and its ignition position is different from J model and Ó model.Dimensionless area is adopted to characterize shape of bubble under effect of shock and combustion. It shows that simulation of bubble area is closely related to chemical reaction model after stage of heat release,and J model has the highest dilation rate. In simulating combustion efficiency of long-term RSBI flow field, differences among chemical reaction models are relatively decreased. As ES model fails to reveal ignition position correctly, J model and Ó model are suitable for simulating RSBI.

With empirical electronic theory of solids and molecules (EET), actual model for unit cell of cementite was built. A statistical method was applied to compute valence electron structure (VES) of cementite of θ-Fe₃C with specified number of Fe atoms substituted by alloyed atom of M(Cr, V, W, Mo, Mn). By definition stability factor, stability of alloyed cementite with different type, number and site of Fe atoms substituted were calculated and analysized. It shows that density of lattice electron, symmetry of bonds and bond energy have great influence on stability of alloyed cementite. It is more stable as M substitutes for Fe² than Fe¹. Alloyed cementite is the most stable as Cr, Mo, W and V substitutes for 2 atoms of Fe² at sites of No.2 and 3 or No.6 and 7. Stability of alloyed cementite decreases in order of W, Cr, V, Mo and Mn.

Based on two annular pressure buildup mechanisms, coupling of wellbore heat transfer and formation heat transfer and coupling of gas temperature and gas pressure, we build a calculation model for critical rate in deep high temperature high pressure( HT/HP) gas wells. It takes account of influence of gas well profile, string assembly and fluid properties. The model is solved with programm based on iterative method. Finally, it is applied to a deep HT/HP gas well in Tarim oilfield. Critical rate under several operational modes are calculated and they provide basis for optimum allocation in deep HT/HP gas wells.

A shock-pinned random projection method( SRPM) is proposed. To overcome difficulty of multidirectional propagation,local random projection is applied by introducing a shock indicator along with proper rules for choosing local projection zones around shocks in each reaction step. Numerical experiments are presented. It shows that SRPM is appropriate for detonation waves with multi-directional propagation,which is high-efficient in solving stiff reactive equations and extensible to 3D situations.

Based on drift model which copes with gas-liquid phase slippage and non-uniform distribution along section of wellbore,a coupled temperature-pressure prediction model was established for varied angle gas wellbores considering momentum conservation,conservation of energy and wellbore heat transmission. The model was validated with 15 tested gas wells. The calculation showed satisfying results with average absolute error of 3. 6% which meets engineering requirements.

Chemical nonequilibrium effect on aeroheating environment of hypersonic vehicles is numerically investigated.First,three gas models are considered for comparing chemical nonequilibrium effect on aerodynamic and aeroheating characteristics over a 2D cylinder-blunt body.Then,a 3D sphere-blunt body is taken to further investigate chemical nonequilibrium effect,especially wall catalysis effect on aeroheating environment.It indicates that chemical nonequilibrium effect does not affect pressure significantly,but reduces shock-standoff distance remarkably and, more importantly, post-shock temperature, and hence affects aeroheating environment significantly.Moreover,wall catalysis effect affects aeroheating environment significantly,and thus effective control of this process reduces wall heat transfer considerably.It is concluded that understanding and accurate prediction of chemical nonequilibrium effect are of decisive importance for the design of thermal protection systems (TPS) of hypersonic vehicles.

With finite difference method and Laplace transform,a Laplace transform difference method for well-test problem with one-dimensional seepage flow is proposed.Firstly,time variable is eliminated by Laplace transform.Then the mathematics model is solved with finite difference method.Finally the wellbore pressure or production is obtained with numerical inversion algorithm.A comparison with finite difference method solution and analytic solution shows that the calculating error of Laplace transform difference method is smaller than that of finite difference method,though it consumes more time in each step.Laplace transform difference method has advantages in well-test application since any moment simulation does not rely on other moment result and space grid.

With Monte Carlo simulation,we investigate phase transition of rod-like liquid crystals.Disciplinarian of specific heat with temperature is obtained. The peak in specific heat illustrates temperature of phase transition.Relations between order parameters and temperature are obtained.Phase diagram with different molecular structure parameters is plotted.It shows that as lengths of short rods are equal no biaxial phase exists.

The geometry and electronic structure of charged molecules C₆₀ are studied in the Su-Schrieffer-Heeger (SSH) model.The influence of the charge taken by C₆₀ molecules on their structure and the electronic structures are analyzed.The third-order polarizabilites of C₆₀ molecules with different charge are calculated.

A fast simulation annealing (SA) algorithm for the design of diffractive optical elements (DOE) for uniform illumination is presented.The Tsallis statistic and corresponding utility function are introduced into a hybrid algorithm in which the self-iterative and SA algorithms are combined to enhance the efficiency.Compared with traditional SA algorithm,simulated results show that it saves 99% of time to converge the incident energy into a desired region with the same mean square error (MSE).

Numerical method for stability analysis and transition prediction for supersonic flow around a blunt cone is investigated. In order to meet the required accuracy of the numerical values in the basal flow field, the result of the flow field is obtained by solving Euler equations where the pressure attribution on the surface of the cone is used as the outer edge pressure attribution of the viscous boundary layer. The Rayleigh inverse-iteration method and boundary layer asymptotic expansion method are used to solve the blunt cone boundary layer stability equation to get reliable boundary layer transition data. This method improves the numerical precision, and saves the computation time. It is also useful for stability analysis of blunt cone supersonic flow.

This paper presents a method for sampling six random variables which indicate three emission angles of gamma rays and three gamma rays energies in the simulation test of three photon annihilation of positrons and electrons From the subsamples produced by the sampling mentioned above, frontier distribution and joint distribution about angles and about energies are obtained. Comparing the present results concerned with the known quantum electrodynamics (QED) prediction and experimental data, it is found that the three results are quite in agreement.

The method of complete partition commonly used in the study of physics and other sciences is discussed and a FORTRAN-77 programme of computating the complete partition is given.