The application of a schlieren system to study the interaction between a TEA CO₂ laser beam and a water column

For the first time work has been conducted to obtain the velocity of a shock wave produced by interaction between a TEA CO₂ laser beam and a column of water. The progressive development of the resulting plasma and its effect on the flow field were observed clearly by means of a Schlieren system and a high speed imaging system. The results showed that the velocity of the shock wave can arrive at more than 35 km/s, which was approximately an order of magnitude higher than what was observed previously from the interaction between the TEA CO₂ laser beam and air. These findings are of great value for instances where water is applied as the propellant in laser propulsion.