Detonation Shock Dynamics (DSD) is a detonation propagation methodology that replaces the detonation shock and reaction zone with a surface that evolves according to a specified normal-velocity evolution law. DSD is able to model detonation propagation when supplied with two components: the normaldetonation-velocity variation versus detonation surface curvature and the surface edge angle at the...

The dynamics of one-dimensional, piston-driven hydrogen–air detonations are predicted in the presence of physical mass, momentum and energy diffusion. The calculations are automatically verified by the use of an adaptive wavelet-based computational method which correlates a user-specified error tolerance to the error in the calculations. The predicted frequency of 0.97 MHz for an overdriven pul...

Detonation of a three-dimensional reactive nonisotropic molecular crystal is modeled using molecular dynamics simulations. The detonation process is initiated by an impulse, followed by the creation of a stable fast reactive shock wave. The terminal shock velocity is independent of the initiation conditions. Further analysis shows supersonic propagation decoupled from the dynamics of the decomp...

Inside this Issue 2 Simulation: A Window into the Detonation of High Explosives 3 Modeling of High-Explosive Detonation Performance 5 The Detonation Sandwich 6 Joint DoD/DOE Munitions Technology Development Program—High Explosives 9 New Faces at the Office of Stockpile Stewardship 10 Publication Highlights T you all for your excellent contributions in FY 2011. The Obama Administration and U.S. ...

A high-speed projectile in combustible gas can initiate and stabilize a detonation wave under suitable conditions [1]. In this paper, numerical simulations of projectile induced detonation waves are presented. Using a one-step irreversible reaction model, the transition from shock-induced combustion to stabilized oblique detonation is observed via numerical simulations. An analysis of this tran...

We study the initiation of the detonation in the gravitationally confined detonation (GCD) model of Type Ia supernovae (SNe Ia). In this model, ignition occurs at one or several off-center points, resulting in a burning bubble of hot ash that rises rapidly, breaks through the surface of the star, and collides at a point on the stellar surface opposite the breakout, producing a high-velocity inw...

Detonation waves in gas-filled piping or tubing pose special challenges in analysis and prediction of structural response. The challenges arise due the nature of the detonation process and the role of fluid-structure interaction in determining the propagation and arrest of fractures. Over the past ten years, our laboratory has been engaged in studying this problem and developing methodologies f...

The flame born in the deep interior of a white dwarf that becomes a Type Ia supernova is subject to several instabilities, the combination of which determines the observational characteristics of the explosion. We briefly review these instabilities and discuss the length scales for which each dominates. Their cumulative effect is to accelerate the speed of the flame beyond its laminar value, bu...

* Member Technical Staff † Vice-President ‡ Professor and Chairman £ Professor Abstract Results of a recent investigation in the design of a single flow path combined cycle engine using periodic detonation waves are presented here. Four modes of operation are used in a sample SSTO trajectory in this preliminary design (sketched in Fig. [1]): (1) An ejector augmented pulsed detonation rocket for...

Computational fluid dynamics based solvers have been developed for explosion modeling in hazards analysis. These include a numerical approach to simulate flame acceleration and deflagration to detonation transition in hydrogen-air mixture and two detonation solvers. The former solves fully compressible, multidimensional, transient, reactive Navier–Stokes equations with a chemical reaction mecha...