Hydrodynamic simulations are performed to study Richtmyer-Meshkov instability (RMI) and material ejection at a metal-vacuum interface using a 2D multi-component elastic-plastic hydrodynamic Eulerian code. Effect of material strength on instability development of roughened surface is analyzed, and relationship between amount of ejected material and saturated bubble amplitude is revealed. Finally, based on RMI theory for elastic-plastic solids, theoretical models to describe critical condition of ejecta formation, total amount and maximum velocity of ejecta from unmelted metals are established.

Mesoscale responses of plastic boned explosives (PBX) and grannular HMX under shock loading were investigated with discrete element method(DEM). It shows that for shocked grannular HMX temperature and pressure in grain boundary are much higher than those of inner HMX crystals. In the case of shocked PBX high temperature and pressure regions are mostly located in binder and near parts. Comparisons show that temperature and pressure in grain boundary are effectively reduced by binder.

Discrete element method combined with undiffused two-phase transition model,thermodynamic consistent Helmholtz free energy function,and phase transition kinetics of relaxation equation are used to simulate α-iron phase transition process.Through simulation of phase boundary,Hugoniot relation and free surface velocity profiles are obtained.Wave interaction in loading and unloading process under different pressures is analyzed.Characteristics of loading and unloading wave velocity are acquired.

A two-dimensional elastic plastic hydrodynamics Eulerian code MEPH is applied to simulate micro-jet formation and penetration process of void in sample during shock loading.We focused on forming process of micro-jet.Maximal penetration depth versus key factors such as shock pressure and void diameter is analysed.Theoretical jet penetration is compared with numerical simulations of maximal penertration depth.

We describe a problem that the multifluid dynamic equations are not closed.To solve equations,they must be closed.Existing closing relations are analyzed and an adaptive closing relation method according to sound velocity is given.Numerical example shows that pressure relaxation is also important for pressure equalization in mixed cells.

A two-dimensional elastic and plastic hydrodynamics code MEPH is applied to simulate ejecting process. We focus on the effect of shock pressure and shock risetime on mass ejection from shocked aluminum. It shows that with increase of shock pressure the ejecting factor keeps increasing, but the ejecting factor is not sensitive to the shock pressure. The effect of shock risetime on the mass ejection from shocked aluminum is also investigated. Numerical results agree well with experiments. The mass ejection is sensitive to shock risetime.

A two-dimensional elastic and plastic hydrodynamics Eulerian code MEPH is applied to simulate aluminium ejecting with single defect.We focus on change of maximum ejecting velocity and ejecting factor with different angle and shape.Numerical results are consistent with experiments.

In this parper, the neutronics performance of a solid breeder blanket of a elementary designed fusion-fission hybrid experimental reactor has been studied in one-, two-, three-dimensional analysis and comparison. For being easy to describe the complicated geometry of the Tokamak torus, the neutron and gamma ray coupled transport calculation has been performed with the help of the Monte Carlo code MCNP. For avoiding uncertainties and errors involved in the generation and application of group constants and self-shielding effects, a continuous energy representation of the nuclear data base has been used.The main concern of the study has been the assessment of the spacial distribution of the tritium breeding ratio, the plutonium breeding ratio, and the power density in multi-dimensional configuration and the comparison between One-, two-, three-dimensional global calculation. The role and the limitation of one dimensional calculation has been pointed out.

Using SIMPLE method,we program a code to solve the 3-D incompressible N-S equations. We compute a 3-D step flow as an example problem, compare it with the 2-D step flow results, and analyse the effects of side walls.