Experimental and numerical investigation of shock wave propagation through complex geometry, gas continuous, two-phase media

The work presented here investigates the phenomenon of shock wave propagation in gas continuous, two-phase media. The motivation for this work stems from the need to understand blast venting consequences in the HYLIFE inertial confinement fusion (ICF) reactor. The HYLIFE concept utilizes lasers or heavy ion beams to rapidly heat and compress D-T targets injected into the center of a reactor chamber. A segmented blanket of falling molten lithium or Li{dollar}sb2{dollar}BeF{dollar}sb4{dollar} (Flibe) jets encircles the reactor's central cavity, shielding the reactor structure from radiation damage, absorbing the fusion energy, and breeding more tritium fuel.; Xrays from the fusion microexplosion will ablate a thin layer of blanket material from the surfaces which face toward the fusion site. This generates a highly energetic vapor, which mostly coalesces in the central cavity. The blast expansion from the central cavity generates a shock which propagates through the segmented blanket--a complex geometry, gas-continuous two-phase medium. The impulse that the blast gives to the liquid as it vents past, the gas shock on the chamber wall, and ultimately the liquid impact on the wall are all important quantities to the HYLIFE structural designers.; The work here presents a numerical method called the Transient Shockwave Upwind Numerical Analysis Method for ICF (TSUNAMI). It is a tool for analyzing two-dimensional blast venting in the HYLIFE reactor. TSUNAMI relies on the assumptions of adiabatic and ideal gas behavior by the vapor and immobile liquid to simplify the problem of two-phase shock propagation to a problem of single phase gas dynamics in a fixed, complex geometry.; To validate the accuracy of the numerical method, experimental data for comparison was obtained from the Liquid Jet Array Shock Tube (LJAST). The experiment provided transient pressure data for gas shocks impacting an array of solid cylinders and an array of liquid jets with similar geometry to the HYLIFE blanket. The comparisons showed that the numerical method accurately predicts shock propagation through a cylindrical array. Furthermore, the experiment provided liquid impact data indicating that liquid jets striking the wall impart only Bernoulli stagnation pressures and not waterhammer pressures.; The application of TSUNAMI to the HYLIFE reactor calculations revealed that venting is very dependent on the blanket geometry. Calculations were performed using two types of blanket geometries, one with a hexagonally pack array of cylindrical jets and the other with a slab array. Both geometries resulted in asymmetric wall loading by the blast, but the slab jets received much less impulse than the liquid jets due to less form drag.; The work here also investigated the effect of condensation on shock reflection. A method of integrating the kinetic theory of condensation with transient gas dynamics is presented. The method was applied to the HYLIFE reactor with slab geometry which revealed a negligible effect of condensation due to the lack of condensing surface area.