AN EXPERIMENTAL INVESTIGATION OF SHOCK WAVE-BUBBLE INTERACTION AND REFLECTION HOLOGRAMS OF LONG POLYMER MOLECULES.

A preliminary experimental study was made to determine the behavior of an air bubble subsequent to the impingement of a shock wave or sharp pressure front upon it. An observed feature of the motion is the formation of a liquid jet similar to those created during the detonation of a shaped explosive charge. Two types of bubbles were observed. One is a long air bubble rising in a shock tube partially filled with water. As first shown by G. I. Taylor the upper interface is nearly spherical. The other is a nearly spherical bubble. Jets are observed in both cases and therefore indicate the need to consider this phenomenon in cavitation damage and cavitation hysteresis studies. In view of the significant effects of very dilute solutions of long chain molecules on cavitation, work on a short pulse duration argon laser was done which shows promise as a means of obtaining holographic information on the dynamic behavior of these molecular groups. Operating pressure of the argon gas is found to be important for short optical pulse generation. Methods of obtaining the holograms pertinent to this application are discussed. Author