Phase-field modeling of fracture in liquid

Abstract

Phase-field theory for the description of the overdriven fracture in liquid (cavitation) in tensile pressure wave is developed. Various results from solid mechanics are transferred into mechanics of fluids. Thermodynamic potential is formulated that describes the desired tensile pressure-volumetric strain curve and for which the infinitesimal damage produces infinitesimal change in the equilibrium bulk modulus. It is shown that the gradient of the order parameter should not be included in the energy, in contrast to all known phase-field approaches for any material instability. Analytical analysis of the equations is performed. Problems relevant to the melt-dispersion mechanism of the reaction of nanoparticles on cavitation in spherical and ellipsoidal nanoparticles with different aspect ratios, after compressive pressure at its surface sharply dropped, are solved using finite element method. Some nontrivial features (lack of fracture at dynamic pressure much larger than the liquid strength and lack of localized damage for some cases) are obtained analytically and numerically. Equations are formulated for fracture in viscous liquid. A similar approach can be applied to fracture in amorphous and crystalline solids. Phase-field theory for the description of the overdriven fracture in liquid (cavitation) in tensile pressure wave is developed. Various results from solid mechanics are transferred into mechanics of fluids. Thermodynamic potential is formulated that describes the desired tensile pressure-volumetric strain curve and for which the infinitesimal damage produces infinitesimal change in the equilibrium bulk modulus. It is shown that the gradient of the order parameter should not be included in the energy, in contrast to all known phase-field approaches for any material instability. Analytical analysis of the equations is performed. Problems relevant to the melt-dispersion mechanism of the reaction of nanoparticles on cavitation in spherical and ellipsoidal nanoparticles with different aspect ratios, after compressive pressure at its surface sharply dropped, are solved using finite element method. Some nontrivial features (lack of fracture at dynamic pressure much larger than the liquid strength and lack of localized damage for some cases) are obtained analytically and numerically. Equations are formulated for fracture in viscous liquid. A similar approach can be applied to fracture in amorphous and crystalline solids.

Mechanochemical mechanism for reaction of aluminium nano- and micrometre-scale particles

“…The solution is confirmed by finite-element simulations [17]. The magnitude of p max increases in inverse proportion with the shell fracture time.…”

“…As c = 4166 m s −1 , t p = 10 ps for R = 41.66 nm. We found from phase-field [17] and molecular-dynamic modelling [18] that cavitation starts in the reflected wave in the central region of a particle. The maximum tensile (negative) pressure at the centre of the particle in the reflecting wave, p max , is…”

Comment on “In situ imaging of ultra-fast loss of nanostructure in nanoparticle aggregates” [J. Appl. Phys. 115, 084903 (2014)]

“…As it was mentioned in Ref. 4 and obtained in phase field simulations, 15 after spallation of the shell the unloading wave may not disperse the Al core but produce a spherical ring. Further dispersion can be caused by a collision with other liquid rings or Al or oxidizer particles, the interaction with gas flow, or a large temperature rise during initiation of the oxidation reaction at the bare surface.…”

Inferring pore connectivity from sorption hysteresis in multiscale porous media

“…Liquid cavitation and fracture under tensile stress has long been a topic of interest [69,70,71,72,73]. One tantalising prospect is the use of experiments like those cited in this work to measure the bulk cavitation relative pressure h n (∞) for various fluids as a function of temperature.…”