With gas-kinetic unified algorithm (GKUA) based on Boltzmann equation for various flows regimes, rotational non-equilibrium effect is investigated in Rykov model, in which spin movement of gas molecules is described with moment of inertia. Numerical method of Boltzmann model equation involving rotational non-equilibrium effect is developed. Nitrogen shock wave structure, flows around a 2D blunt-head body and flows around a 3D tine bicone are simulated to validate the method in various flows regimes.

To investigate effect of rotational degree of freedom on gas flows covering various flow regimes,Boltzmann-Rykov model is studied and reduced velocity distribution functions are introduced with quadrature to rotational degree of freedom of molecular velocity distribution function.A single gas-kinetic model equation is translated into simultaneous equations of three reduced velocity distribution functions at discrete velocity ordinate points with discrete velocity ordinate method and numerical integration technique.One-and two-dimensional Boltzmann-Rykov model equations for diatomic gases are computed with finite-difference method of computational fluid dynamics.One-dimensional shock-tube and the two-dimensional flow past erect plate are analyzed in the whole range of Knudsen numbers.Reliability of gas-kinetic unified algorithm(GKUA) is validated in solving one-and two-dimensional flows from free molecular flow to continuum regimes.It is indicated that the gas rarefaction degree and molecular inner degree of freedom affect flow field greatly.And rarefied gas flows with high Knudsen numbers take serious non-equilibrium effect.

An in-core fuel management code package HEX-ICFM is developed for Xi'an Pulsed Reactor.The orthogonal design model and the loading pattern optimization program HEX-ORTH are studied.The cell calculation is performed using WIMS-D/4.A two dimensional hexagonal geometry multigroup nodal theory code SIXTUS-2 is used for core diffusion calculation.The core physical parameters are calculated using HEX-ICFM for the first cycle of Xi'an Pulsed Reactor.With the fuel of end of cycle 3 and 30 fresh fuel rods the optimum loading patterns are calculated for the objective function max(K^BOC_eff)using HEX-ORTH.

The sampling method by coupling criticality source direction biasing and the exponential transform is established for duct shielding calculation.In sample problem studying,the optimal source direction biasing parameter p₁、exponential transform parameter p₂ are supposed and the variance of duct calculating results by using this method is shown to reduce efficiently.Correction calculation for the duct of Nuclear Power Institute of China (NPIC) pulsed reactor shows the results are more close to the measured ones.

By using lattice calculation code WIMS-D/4,hexagonal nodal diffusion code SIXTUS and the WIMS-N1/N2 library which include the data of the nuclide H in ZrH,Er-166 and Er-167,nuclear safety parameters are analyzed of uranium zirconium hydride pulsed reactor core,power peaking factor and fuel temperature coefficient.

Physical property parameters of oil gas reservoir(i.e.reservoir parameters) are important in reservoir description. Considering both the complexity of finding reservoir parameters by seismic data and the shortages of the nonlinear mapping of BP network which needs complete sample information and is the low effciency of learning.This paper presents a method combining Complete Utilization of Sample Information (CUSI) with genetic algorithm(GA) to calculate these parameters.

The continuous medium mathematical modeling of two-dimensional unsteady transonic two-phase reactive flow of explosive particles in high-loading beds is investigated. The SIMPLE method is successfully utilized for two-dimensional numerical calculation of the Defagration-to-Degonation Transition (DDT) processes in high-loading explosive beds. Special treatment for transonic flow and derivation of pressure correction equation for compressible fluid are presented. As an example, the calculated results for non-primary-explosive detonator show that this method weakens the numerical oscillation of transonic 2D-two-phase flow more effectively.