Date:
Wed, 01/03/201712:00-13:30
Location:
Danciger B building, Seminar room
Lecturer: Dr. John M. Kolinski
Affiliation: Racah Institute of Physics,
The Hebrew University of Jerusalem
Abstract:
A water bell forms when a fluid jet impacts upon a target and separates into a 2-dimensional sheet. Here, we use a custom target system to dynamically alter the separation angle, and study the dynamics of water bells of arbitrary geometry. We find that the water bell’s geometry strongly influences the dynamical response of the driven water bell. Our calculation of the dispersion relation of the fluid sheet predicts geometry-controlled growth of applied perturbations, and our experiments agree with the calculations over a wide range of frequencies and geometries for small forcing amplitudes. At larger forcing amplitudes the water bell’s response changes drastically, and undergoes a transcritical bifurcation at a critical forcing amplitude. The wave dynamics in this regime nevertheless obey the linear dispersion relation.
Affiliation: Racah Institute of Physics,
The Hebrew University of Jerusalem
Abstract:
A water bell forms when a fluid jet impacts upon a target and separates into a 2-dimensional sheet. Here, we use a custom target system to dynamically alter the separation angle, and study the dynamics of water bells of arbitrary geometry. We find that the water bell’s geometry strongly influences the dynamical response of the driven water bell. Our calculation of the dispersion relation of the fluid sheet predicts geometry-controlled growth of applied perturbations, and our experiments agree with the calculations over a wide range of frequencies and geometries for small forcing amplitudes. At larger forcing amplitudes the water bell’s response changes drastically, and undergoes a transcritical bifurcation at a critical forcing amplitude. The wave dynamics in this regime nevertheless obey the linear dispersion relation.