This is a past event
CADR seminar by Dr. Joanna Mason, National University of Ireland, Galway, Ireland.
This talk introduces two impact problems which originate from intermittent noise and vibration problems in vacuum pumps, and unpredictable silence in church bells.
The first part of my talk will concentrate on a gearing mechanism, which was found to be the source of the noise in the vacuum pumps. An impact model is used to describe a pair of meshing gears, where the discontinuities in the model arise from the backlash between the gear teeth. To gain insight into the underlying dynamics, a classical approach of basin-of-attraction computations, bifurcation diagrams and manifold computations is used in conjunction with the recently developed discontinuity-geometry framework. We find that there is a complex interplay between both smooth and discontinuity-induced bifurcations
The second part of my talk will focus on the Emperor's bell in Cologne Cathedral, Germany, a dramatic example of a church bell that would not ring reliably. An impacting-contact model of a church bell is described, where the bell and clapper are modelled as two coupled pendulums. We outline our numerical methods for investigating the underlying dynamics. Current simulations illustrate that the bell exhibits complex dynamics, including coexisting solutions, quasiperiodicity, and an impact-adding sequence from incomplete to complete chattering.
Everyone Welcome!!
- Speaker
- Dr. Joanna Mason
- Hosted by
- School of Engineering
- Venue
- St Marys 105(156)