The fluid-structure interaction simulation of detonationand shock-wave-loaded fracturing thin-walled structures requires numerical methods that can cope with large deformations as well as topology changes. We present a robust level-set-based approach that integrates a Lagrangian thin shell finite element solver with fracture and fragmentation capabilities with an Eulerian Cartesian detonation s...

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...

Several remarkable Iheoretical and computational properties of reacting shock wave, are both documented and analyzed. Tn particular. for sumciently small heat release or large reaction rate, we demonstrate that the reacting compressible Navicr-Stokes equations have dynamically stahle weak detonations which occur in bifurcating wave patterns from strong detonation initial data. In the reported c...

In this paper, we demonstrate the detailed numerical studies of three classical two dimensional detonation waves by solving the two dimensional reactive Euler equations with species with the fifth order WENO-Z finite difference scheme (JCP 227, 2008) with various grid resolutions. To reduce the computational cost and to avoid wave reflection from the artificial computational boundary of a trunc...

Aims. We present the first full-star three-dimensional explosion simulations of thermonuclear supernovae including parameterized deflagration-to-detonation transitions that occur once the flame enters the distributed burning regime. Methods. Treating the propagation of both the deflagration and the detonation waves in a common front-tracking approach, the detonation is prevented from crossing a...

Abstract: We report experimental studies on the initiation of detonations by hypervelocity projectiles in hydrogen-oxygen-nitrogen mixtures. The experimental facility T5 at Caltech was modified to launch 25-mm diameter projectiles at speeds around 3000 m/s. Flow visualization and pressure measurements are reported for several mixture conditions. A clear transition between shockinduced combustio...

The benefits of using insensitive high explosives (IHE) like PBX 9502 (9502) have been well documented [1]. These desirable features come at a price. The reaction zone is longer for IHEs, thus making them more nonideal. In real world applications, this translates into significant performance problems, such as problems with detonation wave spreading. The speed of detonation propagation is affect...

Detailed simulations of the bifurcation and ignition of an Argon-diluted Hydrogen/Oxygen mixture in the two-stage weak ignition regime are performed. An adaptive meshrefinement (AMR) technique is employed to resolve all relevant physical scales that are associated with the viscous boundary-layer, the reaction front, and the shock-wave. A high-order hybrid WENO/central-differencing method is use...

Design of energetic materials is an exciting area in mechanics and materials science. Energetic composite materials are used as propellants, explosives and fuel cell components. Energy release in these materials are accompanied by extreme events: shock waves travel at typical speeds of several thousand meters per second and the peak pressures can reach hundreds of gigapascals. In this paper, we...