Shock waves structure

Although much as been done, much work remains. Improved material models for anisotropic materials, brittle materials, and chemically reacting materials challenge the numerical methods to provide greater accuracy and challenge the computer manufacturers to provide more memory and speed. Phenomena with different time and length scales need to be coupled so shock waves, structural motions, electromagnetic, and thermal effects can be analyzed in a consistent manner. Smarter codes must be developed to adapt the mesh and solution techniques to optimize the accuracy without human intervention. 

The indicated transition pressure of 15 GPa is in agreement with the published data with shock-wave structure measurements on a 3% silicon-iron alloy, the nominal composition of Silectron. A mixed phase region from 15 to 22.5 GPa appears quite reasonable based on shock pressure-volume data. Thus, the direct measure of magnetization appears to offer a sensitive measure of characteristics of shock-induced, first-order phase transitions involving a change in magnetization. 

When the tube is closed at one end and ignited there, the propagating wave undergoes a transition from subsonic to supersonic speeds. The supersonic wave is called a detonation. In a detonation heat conduction and radical diffusion do not control the velocity rather, the shock wave structure of the developed supersonic wave raises the temperature and pressure substantially to cause explosive reaction and the energy release that sustains the wave propagation. 

Fig. 3.1 Schematic representation of the detonation process and the shock-wave structure (a) as well as the shock adiabat for an explosive and the detonation products (detonation in a stationary state) (b).

Behind the sampler a concentric shock wave structure is formed, which surrounds a zone of silence and ends in a shock wave front called the Mach disk. The interface should be such that the skimmer aperture still lies in the zone of silence for an optimal extraction. 

Zhang-licong, Xu-jingde, Zhang Yulong. (2011) Numerical Simulation Of Shock Wave Structure In Gas Explosion. First IntematUmal Symposium on Mine Safety Science and Engineering, 265-268. 

Numerical Solution of Boltzmann Equation, Fig.1 Shock wave structure in nitrogen for A/ = 15 n = density,... 

Erofeev AI (2002) Study of a shock wave structure in nitrogen on the basis of trajectory calculations of molecular interactions. Fluid Dyn 6 134-147... 

Nitrogen gas was used as a driver in the pressure range from 0.5 MPa to 5 MPa. To realize a single component two-phase thermal equilibrium condition in the low pressure chamber, a certain amount of pure liquid was filled after evacuating the chamber. Such common liquids as distilled water, ethanol, benzene, acetone and refrigerant-11(R-11), were examined, but in the this paper discussions are focused mostly on the results of R-11 and benzene because their shock wave structures are more distinctive due to their relatively high saturated vapor pressure at room temperature. It should be noted that these are both "regular" fluids... 

Theoretical treatments of shock waves in vapour-droplet flows are rare in the literature. Partly dispersed shock waves are discussed by Marble [3] (who made some incorrect deductions concerning the magnitude of the relaxation times), Konorski [4] and Bakhtar and Yousif [5]. Fully dispersed waves dominated by just one relaxation process were treated by Petr [6], but few details of his analysis appear in the paper. No experimental measurement of shock wave structure is available, although the work by Barschdorff [1], and Schnerr [7] shows interesting shock formation patterns and has stimulated the present work. 

Kedrinskii, V.K. Peculiarities of shock wave structure at underwater explosion of spiral charges. PMTF(1980), 5. 

As for me, I v/ould be glad to take part and deliver a lecture, tentatively on the history of shock wave structure theory, with emphasis on new phase formation in general and in shocks. 

Hoover W, Holian B, Moran B, Straub G Shock-wave structure via nonequilibrium molecular dynamics and Navier-Stokes continuum mechanics, Phys Rev A 22(6) 2798-2808, 1980. 

Numerical Solution of Boltzmann Equation, Figure 2 Shock wave structure in nitrogen for Af = 10 / = computed density, n, experiment = experimental density, T = translational temperature, Txx = longitudinal translational temperature, frot = rotational temperature (normalized)... 

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