Water Drop/Bow Shock Interactions.

摘要

The interaction of water drops of diameters in the range of 20 to 200 micrometers with reentry vehicle bow shocks was investigated with a microscope/Q-spoiled laser camera system. A single stream of water drops was generated on the trajectory of a Mach 12 projectile launched from a light gas gun. The microscope/Q-spoiled laser camera was used to obtain high resolution photographs of the nose tip region of the projectile as it encountered the water droplets. An analytic study of the droplet/bow shock interaction was undertaken. Calculations showed that droplets above about 20 micrometers in diameter should remain intact and impact the projectile nose tip in the stagnation region. In the stagnation region droplets of this size should experience little deviation from a straight trajectory (i. e., no sweeping action would be expected). These predictions were confirmed experimentally using the techniques described in this report. (Author)