Prof. Carlo Massimo Casciola
Title of the Lecture:
The nucleation process and its coupling to the macroscale
Prof. Carlo Massimo Casciola is presently the Dean of the Faculty of Civil and Industrial Engineering at La Sapienza University of Rome where he leads a research group based at the Mechanical and Aerospace Department, working on the dynamics of complex flows and the coupling of macroscopic flows with a microstructure. He has given contributions to turbulence, particulate-, polymers-laden, and multiphase flows, micro/nanofluidics through molecular dynamics simulations and free-energy methods, and mesoscale methods (phase field methods and fluctuating hydrodynamics). He received the prestigious ERC Advanced Grant, BIC – Following Bubbles from Inception to Collapse, and recently developed a novel microfluidic chip to study cavitation-enhanced blood vessel permeability thanks to the ERC Proof of Concept grant INVICTUS, IN VItro Cavitation Through UltraSound.
Abstract of the Lecture:
Bubble nucleation is a ubiquitous phenomenon whose prediction proved a formidable task, particularly in the case of water. Here a self-contained model is discussed which is shown able to accurately reproduce data for bulk water over the most extended range of temperatures for which accurate experiments are available . The computations are based on a Ginzburg-Landau model which, as only inputs, requires a reliable equation of state for the bulk free energy and the interfacial tension of the water-vapor system. Rare event techniques borrowed from statistical mechanics allow the determination of the free-energy barrier and the nucleation rate. By consistently including thermal fluctuations  in the spirit of Fluctuating Hydrodynamics, the approach is extended to dynamic conditions in presence of solid walls of different wettability  to allow coupling with fluid motion . The talk will focus on the wall wettability in compliance with the fluctuation-dissipation balance, a crucial point in the context of the fluctuating hydrodynamics theory. Depending on time availability, new, still unpublished results concerning the coupling of nucleation and fluid flow, the effect of micro-confinement, and time-changing thermodynamic conditions will also be addressed.
 F. Magaletti, M. Gallo, C.M. Casciola, Water cavitation from ambient to high temperatures, Scientific Reports 2021, 11 1.
 M. Gallo, F. Magaletti, C.M. Casciola, Thermally activated vapor bubble nucleation: the Landau-Lifshitz/Van der Waals approach, Phys. Rev. Fluids. 2018, 3, 053604.
 M. Gallo, F. Magaletti, C.M. Casciola, Heterogeneous bubble nucleation dynamics, Journal of Fluid Mechanics 2021, 906 10.
 M. Gallo, F. Magaletti, D. Cocco, C.M. Casciola, Nucleation and growth dynamics of vapor bubbles, Journal of Fluid Mechanics 2020, 883.