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November 18, 2021: "The Fluid Mechanics of Lung Clogs in the Bronchioles"

  • November 18, 2021
  • 1:00 p.m.
  • Dr. Francesco Romano, Arts et Métiers Paris Tech / Laboratoire de Mécanique des Fluides de Lille
  • Faculty Host: Olivier Coutier-Delgosha

Abstract: The human lung airways are lined by the airway surface liquid (ASL). The ASL is either a layer of mucus or a two-layer liquid film consisting of the serous (outer) and the mucus (inner) layer. Owing to the Plateau-Rayleigh instability, the ASL can lead to airway closure, i.e. the occlusion of the airway due to the formation of a liquid plug. This is typical of distal airways, namely the bronchioles from the 7th generation onwards. In our simulations we focus on the fluid dynamics phenomena occurring during an airway closure, hence we assume the bronchiles walls as rigid. We isolate several elements of complexity to well comprehend their standalone effect on the airway closure. Indeed, we consider the airway closure with: (i) surfactant in a single-layer film, (ii) viscoelasticity and (iii) elastoviscoplasticity of a single-layer liquid, and (iv) two-layer Newtonian film. Apart from the primary instability leading to aiway closure, we focus on the post-coalescence wall stresses and secondary instabilities due to viscoelastic effects.

Bio: Francesco Romanò is an Associate Professor at Arts et Mètiers. He earned a Bachelor’s and a Master’s degree in Aerospace Engineering at the University of Pisa, Italy, in 2010 and 2012, respectively. In 2016 he completed his Ph.D. in Mechanical Engineering at TU Wien, Austria, with a research focus on Fluid Dynamics, Numerical Methods and Dynamical Systems. During his Ph.D. he also held the position of University Assistant at TU Wien, where he taught a Master’s course for Numerical Methods in Fluid Dynamics for four years. After his Ph.D., he kept being affiliated to the Institute of Mechanical Engineering and Heat Transfer, TU Wien, as University Assistant and Post-Doc Researcher for 1.5 years, mentoring Intern, Bachelor, Master, and Ph.D. students and keeping his teaching activity. In April 2017 he moved to the United States, where he was granted of a Research Fellowship at the Department of Biomedical Engineering, University of Michigan, until August 2019. Since September 2019, he joined the Department of Fluid Mechanics and Energetics at Arts et Mètiers, Lille, where he gives courses of Aerodynamics, Turbomachinery, Heat Transfer and Numerical Methods. His research topics include mixing in cavities, chaos theory, multiphase flows in microfluidic systems (particle-laden and multi-fluids flows), biological flows, non-Newtonian flows, thermo- and soluto-capillary flows, stability analysis, mathematical modelling of complex multiscale systems and, recently, flow control and turbomachinery.