Ricerc@Sapienza

Direct numerical simulations of a bubbly laden homogeneous shear flow have been carried out using the exact regularized point particle method as the inter-phase momentum coupling approach. The aim of this study consists in addressing the modulation of shear turbulence and the bubble clustering geometry in the presence of different inter-phase momentum coupling conditions. Suspensions with different combinations of the void fraction and Kolmogorov-based Stokes number, in the dilute regime, have been addressed. Bubbles suppress the turbulent kinetic energy and turbulent dissipation as well.

Our understanding of decompression physiopathology has slowly improved during this last decade and some uncertainties have disappeared. A better understanding of anatomy and functional aspects of Patent Foramen Ovale (PFO) have slowly resulted in a more liberal approach toward the medical fitness to dive for those bearing a PFO.

In this work we study the existence of nodal solutions for the problem -Δu=λueu2+|u|pinΩ,u=0on∂Ω,where Ω ⊆ R2 is a bounded smooth domain and p→ 1 +. If Ω is a ball, it is known that the case p= 1 defines a critical threshold between the existence and the non-existence of radially symmetric sign-changing solutions. In this work we construct a blowing-up family of nodal solutions to such problem as p→ 1 +, when Ω is an arbitrary domain and λ is small enough.