Shock Induced Symmetric Compression in a Spherical Target

Abstract

Shock induced symmetric compression has been studied in a spherical target. The shock induced interfacial radius will shrink and would reach a minimum point during implosion situation. However, after implosion the plasma tries to expand in blow off/explosion situation and as a result the interfacial radius will increase. Effects of plasma parameters like density and temperature have been studied numerically. It is seen that the density increases many times due to the mass conservation in imploding situation of a compressible shell like ICF. However, temperature will change rapidly due to change of inner density and so would be the pressure of compressible fluid following adiabatic law. Our analytical results agree qualitatively with those of simulation results in spherical geometry and also experimental observations conducted in cylindrical container.

The Post Shock Nonequilibrium Relaxation in a Hypersonic Plasma Flow Involving Reflection off A Thermal Discontinuity

“…However measuring the structure in therms of distance may not show a visible difference, except the intensity. After the transitional period limited with the incident shock relaxation time, the gas state past the transmitted wave will be adjusted accordingly to the new temperature of the medium and can be determined with the relations (5)(6)(7)(8)(9), the experimental data for the energy content factors 𝛽𝛽 𝑎𝑎 , 𝛽𝛽 𝑖𝑖 , and the corresponding factor σ.…”

“…First, the relaxation zone structure of the incident shock is dependent on the Mach number, in accordance to the eqs. (5,6,9). Thus the analysis of the reflection dynamics should account for not only stronger shocks but also that of different structure.…”

“…1. The expressions for the coefficients 𝛿𝛿 1 , 𝛿𝛿 2 , 𝛿𝛿 and 𝜀𝜀 1 , 𝜀𝜀 2 , 𝜀𝜀 3 , 𝜀𝜀 4 , 𝜀𝜀 5 , 𝜀𝜀 6 , 𝜀𝜀 7 , 𝜀𝜀 10 appearing in the equations (5,6): (25)…”

“…The vast pool of applications using plasma media includes aerospace, air flight and environmental domains, that can benefit from the research aimed at: achieving significantly reduced wave drag and thus increased aircraft speed, lowered fuel consumption, and ultimately a longer flight range [1]; the possibility of controlling the direction of a vehicle in flight via energy deposition in the flow around it [2][3][4]; and managing the sonic boom detrimental to the environment. On a laboratory scale, the topics of academic and applied interests include the shock-flame interaction and combustion [5], and the shock-assisted compression utilizing implosion toward the target [6] in fusion research. In astrophysics, the studies are of interest to explain fascinating phenomena occurring, for example, during supernova explosion [7].…”