LAUSR

In this study, the behavior of contrast agents near a wall subjected to ultrasound wave have been studied numerically using boundary integral method. Contrast agents are gas filled microbubbles coated with layer of lipid or protein to prevent them against dissolution in the blood stream. Under the exposure of ultrasound wave, the contrast agents oscillate and collapse. The oscillation or collapse of the contrast agent near a wall generates shear stress resulting in the perforation of the wall to better uptake of large molecules and drugs by the tissue. In this research, we are studying the dynamics of the contrast agent, the surrounding velocity and pressure filed and the shear stress exerted on the wall due to bubble collapse for different shell rheology parameters, different standoff distances, different excitation pressures and frequencies. The study has been conducted at excitation pressures beyond the threshold of inertial cavitation where the bubble forms a jet during the collapse phase. The strain ...