In laser detonation thrusters, laser energy is converted directly into thrust through the Laser Supported Detonation phenomenon. To predict their thrust performance, it is necessary to know the propagation velocity of the LSD wave and pressure rise behind the wave. In this study, LSD wave propagation velocity and blast-wave energy conversion efficiency were measured by experiments. As a result, the measured LSD wave propagation velocity was found much lower than the calculated velocity in CFD. The blast-wave energy conversion efficiencies measured in air and Ar at 1.0 atm were 45% and 48%, respectively, and the laser energy transfer efficiency is considered to be approximately equal to those efficiencies. On this background, a CJ detonation solution can exist in the Hugoniot analysis when approximately 85% of the transferred laser energy is assumed to flow out in the radial direction on the center axis of the beam. In addition, it was suggested that a twodimensional analysis was needed to have a quantitative agreement in LSD propagation velocities between measurements and CFD analyses.
