OBJECTIVE: Shock Wave Lithotripsy (SWL) is the use of shock waves to fragment kidney stones. We have undertaken a study of the physical mechanisms responsible for stone comminution and tissue injury in SWL. SWL was originally developed on the premise that stone fragmentation could be induced by a short duration, high amplitude positive pressure pulse. Even though the SWL waveform carries a prom...

The cavitation phenomenon is an important factor affecting the safe and stable operation of hydraulic machinery units. units can lead to increased vibration, reduced efficiency, erosion blades. Therefore, a method needed determine incipient runner This study initiated from acoustic characteristics bubbles generated by model turbines radiated sound energy during cavitation. noise are studied. Af...

AN INVESTIGATION OF SURFACE RE-FORMATION IN THE PRESENCE OF INERTIAL (TRANSIENT) CAVITATION (GR/N30989/01) P. R. Birkin and T. G. Leighton 1. Background There is an international need to understand the influence of inertial (transient) cavitation on the erosion of surfaces. Electrochemical data, relevant to this area, has been concentrated on the bulk effects observed for relatively large elect...

Cavitation in solid-water mixtures generated by ultrasonic waves can be used to modify the topography of metallic surfaces. During ultrasonic irradiation two kinds of processes occur in the liquid: (a) material removal by bubble formation plus collapse and the resulting micro jets; (b) material removal by colliding or sliding of accelerated particles due to bubble formation plus collapse. Both ...

Cavitation erosion is induced by the penetrating pressure from implosion of cavitation bubbles nearby solid boundary. The bubble evolution and subsequent collapse are especially important to evaluate degradation boundary materials. dynamics equation taking into account influence distance between formulated investigate effect wall on process. fluctuation slapping forces adopted dynamic character...