Ignition and growth of a detonation by a high energy plasma

Abstract

Abstract. Many experimental and numerical studies have been achieved to describe the transition process of deflagration to detonation when a projectile impacts an explosive. Also a large work has been done for the determination of various parameters -such as the impact pressure, the efficiency factors, etc. of the laser -material interaction. When a laser beam impacts an explosive, the p2~. criterion, characteristic of shock initiated detonations, is no longer valid due to the generated hot plasma whose effect is to decrease the DDT (Deflagration to Detonation Transition) duration. The present paper deals with a modelling of the plasmaexplosive medium allowing the determination of distances and times of the DDT process. The two phase modelling of the granular explosive takes into account the creation of hot spots. The pressure of the plasma is computed using a semi empirical model, while the temperature is obtained from Maxwell Boltzmann statistics. The authors focused their attention on the equation of state for the detonation products and the numerical process.

A Multiphase Godunov Method for Compressible Multifluid and Multiphase Flows

“…Only a few attempts to do this exist in the literature. They are related to studies on detonation waves in granular materials (Butler et al [7], Powers et al [30], Saurel et al [36]). In these works, the various models were not suitable for solution of interface problems, which is why we have built a new model that allows the treatment of interface problems, as well as homogeneous two-phase flows.…”

A High-Resolution Numerical Method for a Two-Phase Model of Deflagration-to-Detonation Transition

“…Most commonly used numerical methods for simulating DDT are based on either conventional method of lines (MOL) or MacCormack predictor/corrector techniques, relying on explicitly added artificial viscosity to capture shocks and maintain numerical stability [3,4,8,46,54]. It is likely that this added viscosity reduces the ability of such methods to accurately resolve fine-scale detonation structure due to excessive numerical smearing.…”

Extension of some numerical schemes to the analysis of gas and particle mixtures

“…Similar approaches can be found in Combe and Hérard [9], Krispin and Collins [10], Toro [11], Rogue et al [12], and Saurel et al [13]. Instead of adding this term, some authors include this effect in the solid pressure by means of a stress 848 J. R. GARCÍA-CASCALES, J. MULAS-PÉREZ AND H. PAILLÈRE tensor in such a way that…”