Parametric study on the shock wave energy of bubble collapse near an elastic membrane

This study presents experimental observations of the shock wave resulting from a single bubble collapsing near an elastic membrane. Based on hydrophone measurement, the pressure peak (pmax), the collapse shock wave energy (Es), and the normalized shock wave energy (Es/E0) are obtained. The effects of dimensionless distance (γ), liquid condition (i.e., density ratio of the liquids on both sides of the membrane, α) and membrane properties (thickness, T, and elastic modulus, E) on pmax and Es/E0 are investigated. In most cases, both pmax and Es/E0 show similar trends, initially decreasing and then increasing as γ decreases. While for the membrane with a relatively low elastic modulus (E = 0.6 MPa), both pmax and Es/E0 tend to decrease with decreasing γ. The γ values corresponding to the minimum pmax are lower than those reported for a rigid boundary. The differences in pmax and Es/E0 due to α are significant at γ > 1.5. Moreover, the γ values corresponding to the minimum pmax and Es/E0 both increase with increasing T and E.