By using temperature-and-density dependent atomic models, a method for uncertainty of electron EOS of plasmas is described via 35 functional exchange-correlation potentials. A fast method for roughly evaluating uncertainty is designed, and checked in Thomas-Fermi model. Taking gold as an example, calculations of uncertainties of total inner energy, electron pressure and ionization degree, with their ‘quasi true value’, are carried out in the range of temperatures from 1.0 to 10 000.0 eV with three densities 1.0, 10.0, 100.0 g·cm^-3,respectively. The results can be applied in engineering design.

We study uncertainty in blast wave problem. Input uncertainties are characterized as aleatory and epistemic uncertainties. Mixed UQ approaches are employed. The outer level UQ is linked to epistemic uncertainty, and the inner UQ is linked to aleatory uncertainty. Non-intrusive polynomial chaos (NIPC) is utilized to cope with aleatory uncertainty. Dempster-Shafer structure is used to deal with epistemic uncertainties. Upwind scheme is used to solve corresponding deterministic system. It acquires preferably effect. It is shown that NIPC approach and Dempster-Shafer structure handles efficiently effect of initial-boundary value uncertainty and parameter uncertainty on simulation result. It is helpful in evaluating degree of confidence and validating result of modeling and simulation.

Main cause for uncertainty of atomic structure theory is indicated. A method for uncertainty of temperature-and-density-dependent atomic models in radiative opacity calculation is described via various functional exchange potentials. Uncertainty quantification(UQ) calculation of atomic structures in density-functional at arbitrary temperature and density is carried out by definition of algorithms of modulus. Several procedures indispensable for uncertainty study, and formulae about UQ of electron energy levels and of matrix elements are given. A criterion is proposed to estimate atomic models quantificationally. Feasibility of UQ method is verified by of data of mercury, gold and iron compared with data from‘quasi true’atomic model.

We introduce asymptotic order of convergence,asymptotic range of convergence and concepts under behavior of Lagrangian computations.We also introduce grid convergence index to Lagrangian computation,and give a program using GCI method.These concepts and methods are used to measure computed values away from numerical asymptotic values.

We present a closed void interface method for computational models with void interface in multi-material problems.It simulates void successfully in complicated engineering.It bases on a technique of changeable mesh topology.It avoids using a straight line to replace a curve in traditional method,and overcomes difficulty in solving contact points.Numerical simulations confirm that the technique is effective.It shows characteristic of no void connectivity.

We present a reconection-based Lagrangian+rezone(LR) method,in which connectivity of meshes can be changed in a rezone phase in order to handle geometric intersection.The method maintains more Lagrangian features of meshes than standard LR methods.Numerical examples demonstrate that the method is more robust for large defomations.It shows predictive capabilities of reconnection-based LR method.

High-energy explosive detonation diffraction is simulated with a 2D Lagrangian unstructured mesh detonation fluid program. With EOS of JWL and trinomial reaction rate, numerical result by Lagrangian program agrees with experimental result qualitatively. Phenomena of whirlpool is well simulated. Desensitization is added to reaction rate in simulation of dead zone in insensitive high explosives detonation diffraction. The dead zone is captured. The result agrees with reported data qualitatively.

With artificial viscosity and total variation diminishing advection limiter, the edge-centered artificial viscosity with structure zones is extended to unstructured grids, The limiter is constructed by neighbor edges determined by maximum angle choice. The edge-centered artificial viscosity is compared with the zone-centered artificial viscosity. Numerical results demonstrate accuracy and efficiency of the edgecentered artificial viscosity in capturing shock discontinuous.

A structured grid generation method for domains with complicated boundary is discussed.Based on the Winslow method with variational form,and combined with grid untangling and area averaging technologies,a discrete functional is designed. The minimization of the discrete functional is solved by an optimization algorithm,and good grids are generated.Numerical experiments show that the method is robust and generates grids with good geometric qualities on complicated domains.This method inherits advantages of the Winslow method and overcomes some faults.

The subzonal pressure is obtained with subzonal Lagranian masses and corresponding densities. It results in subzonal corner forces and eliminates hourglass motion and spurious vorticity.We extend the compatible Lagranian hydrodynamics algorithm including subzonal pressures to unstructured zone and develope the code.Numerical examples of Saltzman piston demonstraste that this algorithm captures shock discontinuity,eliminates hourglass motion and restraines spurious vorticity accuratly and efficiently.

Based on Noh's artificial viscosity with artificial heat flux method(Q & H),we present a Q & H scheme on arbitrary n-polygon meshes.Noh's Q & H on structured meshes is extended to unstructured meshes in two dimensions.Numerical results of Noh's problem and collision of two metals show that the Q&H method on unstructured meshes eliminates wall heating effectivly.

A scheme for unstructured quadrilateral mesh generation based on Delaunay triangulation is presented.With a front edge definition we mark a triangle mesh in the front edge.According to triangle mesh shape and directionality two triangular meshes are merged into a quadrilateral mesh. A 100% quadrilateral mesh obtained converts a quad-dominant to an allquad mesh with mesh conversion templates.Numerical results are shown.

Based on the MT(Multipole Theory),a new method is presented for calculating the electrical conductance of cables with complicated cross-section.By analyzing two examples, it is proven that the calculating accuracy of the MT is much better than that of the BEM(Boundary Element Method).