BACKGROUND A noninvasive technique to monitor thermal lesion formation is necessary to ensure the accuracy and safety of high-intensity focused ultrasound (HIFU) treatment. The purpose of this study is to ultrasonically detect the tissue change due to thermal coagulation in the HIFU treatment enhanced by cavitation microbubbles. METHODS An ultrasound imaging probe transmitted plane waves at a...

Abstract The asymmetric collapse of cavitation bubbles near a solid substrate generates large wall shear stresses, the precise magnitude which is still not known with certainty. By comparing numerical simulations and experiments laser‐induced bubble substrate, we demonstrate that an accurate measurement pressure pulse emitted during inception maximum radius allow unique initialisation simulatio...

Side channel pumps are extremely prone to cavitation, and the internal exchange flow between impeller side induces numerous vortical structures that causes significant energy loss. Therefore, it is important investigate cavitation characteristics loss in under cavitating conditions. This paper investigates a pump using scale-adaptive simulation turbulence model coupled with Zwart model. The dev...

Experimental instantaneous shadowgraph visualizations on transparent glass nozzle replicas of high-pressure fuel injectors have been used to validate a novel in-house high-fidelity LES-VOF multiphase solver, study the evolution vortex flow and cavitation. Both experiments simulations capture formation an unsteady vapor structure inside volume, which is referred as ‘string-cavitation’; strings a...

In many cavitating liquid flows, when the number and concentration of the bubbles exceeds some critical level, the flow becomes unsteady and large clouds of cavitating bubbles are periodically formed and then collapse when convected into regions of higher pressure. This phenomenon is known as cloud cavitation and when it occurs it is almost always associated with a substantial increase in the c...

For high-performance foiling yachts, cavitation is often a limiting factor for take-off and top speed. The present work investigates solutions to control the onset of thanks combination leading edge trailing flaps. Numerical experiments in hydrodynamic tunnel are conducted order assess effect specific geometric parameters on performance inception. hydrofoils manufactured using an additive 3D pr...