We present some numerical results for the linear dynamics of nanobeams modulated by an axial force, basing on a recent proposal of literature that encompasses both the standard nonlocal elasticity, according to Eringen, and second-order strain elasticity. Three different possibilities for the elastic potential energy provide different responses that highlight the contributions of nonlocality and strain gradient, plus their combination. An axial force affects the linear stationary dynamics of such nanobeams, inducing suitable variation of the natural angular frequencies for benchmark cases, until static buckling occurs when the natural angular frequency vanishes. Effects of the various elastic potentials on this modulation are investigated and thoroughly commented.

We discuss the interaction of the strongly nonlinear fluid motion induced by the collapse of a vapor microbubble over a planar surface and the elastic dynamics of the underlying solid. The fluid is described using an extension of the Navier-Stokes equations endowed with distributed capillary stresses in the context of a diffuse interface approach. The collapse of the bubble is triggered by overpressure in the liquid and leads to an intense jet that pierces the bubble, changing the bubble topology from spheroidal to toroidal, and impinges the solid wall inducing an intense and strongly localized load. Moreover, at bubble collapse, a compression wave is launched into the liquid surrounding the bubble. By propagating along the solid surface, the compression wave combined with the liquid jet excites the dynamics of the elastic solid, producing a complex system of waves, including, longitudinal, transversal, and Rayleigh waves, propagating in the solid. It is conjectured that the intense deformation of the solid induced by the strongly localized liquid jet may lead to the plastic deformation of the solid producing the surface pitting observed in many applications subject to cavitation-induced material damage.

In the present work, a diffuse interface model has been used to numerically investigate the laser-induced cavitation of nano/microbubbles. The mesoscale approach is able to describe the cavitation process in its entirety, starting from the vapor bubble formation due to the focused laser energy deposition, up to its macroscopic motion.In particular, the simulations show a complete and detailed description of the bubble formation and the subsequent breakdown wave emission with a precise estimation of the energy partition between the shockwave radiating in the liquid and the internal energy of the bubble. The scaling of the ratio between the energy stored in the bubble at its maximum radius and the one deposited by the laser is found in agreement with experimental observation on macroscopic bubbles.

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The original version of this book was inadvertently published without including a chapter 12. The chapter 12 titled "Vapor Nucleation in Metastable Liquids The Continuum Description" has been added at the end of the book.