Prediction of blast wave effects on a developed site

The guidelines for protecting against and mitigating explosion hazards require knowledge and either the experimental or theoretical evaluation of blast wave parameters. To this end, this article proposes a numerical method for simulating blast wave propagation in complex geometries. This method permits an on-the-ground TNT-like explosion and the subsequent blast wave to be simulated, with the possibility of modifying the ground topology by adding a number of obstacles. The numerical model is explored from both a qualitative and quantitative point of view by comparing it to experimental data, with a correct determination of the wave amplitude and phase signature at different key-positions. The pressure and Mach number distributions deduced from simulations in complex congested areas highlight various fluid–solid interactions, such as regular reflections and diffractions. The iso-damage diagrams of different obstacle layouts are also presented and discussed.     

ĽEdi,entre informatisation et communication

Based on data gathered from a first Edi experiment initiated in various industrial and service sectors, this paper tries first to locate the actual level of accomplishment beyond what is declared. A second step will be to identify some important questions raised by these experiments in the field of industrial activity and in economic changes in progress with the concerned companies. It is shown that merging Edi and just-in-time brings new behavioural stiffness. Also global quality policy associated with Edi raises new demands concerning risks management.     

Efficient 3D numerical prediction of the pressure wave generated by high-speed trains entering tunnels

The topic of this paper is to present a new methodology for the three-dimensional numerical simulation of the entrance of high-speed trains in a tunnel. The movement of the train is made thanks to a technique of sliding meshes and a conservative treatment of the faces between two domains. All parts of the development are thought with the aim to reduce the computational time. In particular, non-reflecting boundary conditions for non-structured three-dimensional meshes are developed in order to limit the calculation domain. Validations of the methodology are presented on different test cases.