Scaled impulse loading for liquid hydraulic response in IFE thick-liquid chamber experiments

In an inertial fusion energy (IFE) target chamber using thick-liquid protec tion. placing liquid surfaces close to the fusion target helps to reduce pu mping cost and final-focus stand-off distance. The impulse loading generate d by the target on the adjacent jet surfaces provides the most important bo undary condition for the subsequent liquid hydraulic response, pocket disru ption, droplet generation, and pocket clearing and regeneration. However, l iquid jets are difficult to use in current X-ray facilities that can simula te the X-ray ablation process. Instead, it is desirable to study liquid hyd raulic response using water jets, employing scaled impulse loads delivered by chemical detonations or shock tubes. Because the pressure load generated by IFE targets is extremely short compared to the time required for signif icant liquid motion, only the time integrated impulse load is important to the liquid motion, not the detailed pressure history from ablation and vent ing. In this work, this impulse loading is determined using the 2-D gas dyn amic code, TSUNAMI, and a comparison made between the impulse loads generat ed by IFE targets and by scaled chemical detonations. (C) 2001 Elsevier Sci ence B.V. All rights reserved.