Viscous Jet Instabilities

This lecture covers the destabilization of a jet, dispersion relation, viscosity-dominated flows, surface tension effects, eigenmodes of viscous jets, and fundamental solutions for boundary conditions. It discusses the global and local stability of flows, emphasizing the importance of absolute instability. The presentation includes equations from Eggers and Dupont (1994) and Rayleigh (1892), as well as the non-dimensionalization of the governing equations. The instructor explains the implications of surface tension on jet stability and the conditions for global instability. The lecture concludes with a detailed analysis of eigenmodes and absolute frequencies in viscous jet flows.