Abstract. We have investigated the design windows for attractive laser fusion reactors. As the feasibility of liquid chambers strongly depends on the liquid metal ablation and evacuation process, we have developed a simulation code on ablation, in which we consider the energy absorption of charged particles with ablated liquid vapors, using the stopping power obtained by dielectric functions of plasmas. And we have developed an evacuation code using DSMC method, which solves the Boltzmann equation. We estimated the ablation depths of liquid surfaces, which depend on the fusion pulse energies, the chamber radiuses, and the energy absorption with ablated vapors. And we evaluated the evacuation speeds limiting the chamber design windows. Based on these estimations we have started a new design study, KOYO-Fast using the fast ignition concepts, under the basic specifications of 200 MJ fusion pulse energies, 3 Hz fusion pulse rep-rates in a liquid wall chamber concept, and 15 Hz laser rep-rates for multi-reactors-modular-plants.
IAEA 2003