The study on deflagration-to-detonation transition (DDT) is very important because this mechanism has relevance to safety issues in industries, where combustible premixed gases are in general use. However, the quantitative prediction of DDT is one of the major unsolved problems in combustion and detonation theory to date. In this paper, the DDT process is studied theoretically and the critical ...

Thrust from a multicycle pulse detonation engine operating at practical flight altitudes will vary with surrounding environment pressure. We have carried out the first experimental study using a detonation tube hung in a ballistic pendulum arrangement within a large pressure vessel to determine the effect that the environment has on the single-cycle impulse. Air pressure decreased below 100 kPa...

The detonation of a CHNO explosive was used for the first time to synthesize carbon nanotubes effectively at low pressure and temperature by introducing a cobalt catalyst and/or paraffin into the detonation system.

Oblique detonation stability was studied by numerically integrating the two-dimensional. one-step reactive Euler equations in a generalized, curvilinear coordinate system. The integration was accomplished using the Roe scheme combined with fractional stepping; nonlinear flux limiting was used to prevent unphysical solution oscillations near discontinuities. The method was verified on oneand two...

An optical system has been redesigned and used to measure detonation velocity as a function of condensed explosive density for RDX, HMX, PETN. These measurements are then used to determine and fine tune parameters appearing in the BKW (Beker-Kistiakowsky-Wilson) equation of state for gases at extremely high pressures. Steady state form of conservation equations along with the BKW state equation...

INTRODUCTION TYPES OF NUCLEAR AND RADIOLOGICAL EXPLOSIVE WEAPONS MEDICAL EFFECTS OF NUCLEAR WEAPON DETONATION URBAN CASUALTY AND DESTRUCTION PATTERNS AFTER THE LOW-ALTITUDE NUCLEAR DETONATION AT HIROSHIMA CURRENT PROJECTIONS OF URBAN CASUALTY, DESTRUCTION, AND FALLOUT PATTERNS AFTER A GROUND-LEVEL NUCLEAR DETONATION PERSONAL PROTECTION AND LONG-TERM HEALTH RISKS FOR EMERGENCY RESPONSE PERSONNEL...

In the context of explosion models for Type Ia Supernovae, we present one-and two-dimensional simulations of fully resolved detonation fronts in degenerate C+O White Dwarf matter including clumps of previously burned material. The ability of detonations to survive the passage through sheets of nuclear ashes is tested as a function of the width and composition of the ash region. We show that det...

Previous works (Daubech et al., 2019) were dedicated to gaseous flame acceleration along long pipes with a set of cases studied both experimentally and numerically. In these cases, the flammable mixture was initially quiescent homogenously distributed. The impact tube diameter material trough approaches for rather slow flames, fuel being methane. While main features real recovered by chosen CFD...

Comparisons between direct numerical simulation (DNS) of detonation and detonation shock dynamics (DSD) is made. The theory of DSD defines the motion of the detonation shock in terms of intrinsic geometry of the shock surface, in particular for condensed phase explosives the shock normal velocity, Dn, the normal acceleration, Ḋn, and the total curvature, κ. In particular, the properties of thre...

This report describes experimental studies and analyses on the detonation properties of flammable gases that may be present in the waste storage tanks at Hanford, WA. These studies were carried out in the Explosion Dynamics Laboratory, part of the the Graduate Aeronautical Laboratories of the California Institute of Technology (GALCIT). Detonation cell sizes and pressures were measured in the G...