Collapsing bubbles in complex geometries
Lead Research Organisation:
University of Southampton
Department Name: Sch of Engineering
Abstract
One of the most violent free surface flows is the collapse of a cavitation bubble. The focusing of energy in such a collapse is strong enough to damage ship propellers, but can also be used to clean surfaces or enhance chemical reactions. The way that a bubble collapses depends on the type and the shape of the materials in the vicinity of the bubble. The aim of this project is to address a basic fundamental aspect of this energy focusing mechanism, by investigating the influence of complex surrounding geometries on the collapse of single bubbles. These findings can in the longer term be applied to make more efficient use of bubbles, for example in the ultrasonic cleaning of complex 3D-printed structures.
In this project you will use a variety of experimental techniques, which include laser-induced cavitation, high-speed imaging, and particle image velocimetry. The candidate should have a background in physical sciences or engineering and have an interest in fluid dynamics.
In this project you will use a variety of experimental techniques, which include laser-induced cavitation, high-speed imaging, and particle image velocimetry. The candidate should have a background in physical sciences or engineering and have an interest in fluid dynamics.
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/R513325/1 | 01/10/2018 | 30/09/2023 | |||
| 2281992 | Studentship | EP/R513325/1 | 01/10/2019 | 30/09/2022 | Elijah Andrews |
| Description | Firstly, we have experimentally shown how a rectangular channel cut into a flat surface (a 'slot') affects a nearby collapsing bubble. When the bubble collapses a jet is formed which would usually be directed straight toward a nearby surface. However, our experiments show that the jet angles away from a slot. We developed a numerical model that also shows this behaviour and validated it against our experimental data. This allowed us to quantify the relationship between slot geometry and bubble collapse. Secondly, we further developed the numerical model to predict the magnitude of the collapse, measured as the displacement of the bubble. Experimental data showed that this model predicted displacement well. Finally, we used experiments and our numerical model to investigate porous plates: thin, rigid plates with patterns of through-holes. We showed that the bubble displacement decreased as the proportion of the plate covered by holes increased. We further showed interesting interactions between the bubbles and the holes, and identified some key regimes of bubble collapse behaviour. |
| Exploitation Route | These impacts are primarily academic, providing significant contributions to the field of cavitation in complex geometries which has received much interest in recent years. Our numerical model is very simple, and could be similarly applied to many other geometries. This can be done with good confidence as it has been experimentally validated. In addition, the insights into bubble behaviour gained from this research so far form a solid base from which to analyse other geometries. |
| Sectors | Other |
| Title | Data for "Cavity collapse near slot geometries" |
| Description | Bubble collapse data (movies and analysed data therein) supporting the "Cavity collapse near slot geometries" paper. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2020 |
| Provided To Others? | Yes |
| Impact | This data is the experimental foundation of the "Cavity collapse near slot geometries" paper. |
| URL | https://eprints.soton.ac.uk/441870/ |
| Title | Data for "Modelling bubble collapse anisotropy in complex geometries" |
| Description | Dataset in support of the journal article "Modelling bubble collapse anisotropy in complex geometries". |
| Type Of Material | Database/Collection of data |
| Year Produced | 2022 |
| Provided To Others? | Yes |
| Impact | Dataset supports a publication. |
| URL | https://eprints.soton.ac.uk/471783/ |
| Title | Model for "Cavity collapse near slot geometries" |
| Description | The Boundary Element Method model developed for the "Cavity collapse near slot geometries". This is packaged in the same zip archive as the dataset also reported. |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2020 |
| Provided To Others? | Yes |
| Impact | This is the numerical model developed and validated as part of the "Cavity collapse near slot geometries" paper. |
| URL | https://eprints.soton.ac.uk/441870/ |
| Title | Model for "Modelling bubble collapse anisotropy in complex geometries" |
| Description | Model in support of the journal article "Modelling bubble collapse anisotropy in complex geometries". |
| Type Of Material | Computer model/algorithm |
| Year Produced | 2022 |
| Provided To Others? | Yes |
| Impact | Model supports publication. |
| URL | https://eprints.soton.ac.uk/471783/ |
| Description | Fernandez Twente |
| Organisation | University of Twente |
| Country | Netherlands |
| Sector | Academic/University |
| PI Contribution | Experimental work lab, modelling work, intellectual input, primary investigation, paper writing. |
| Collaborator Contribution | Expert advice, insight into applications of the research area, input and advice on paper writing and editing. |
| Impact | DOI: 10.1017/jfm.2020.552 |
| Start Year | 2019 |