A discussion is given of numerical techniques for modelling fluid flows with free surfaces, covering the basic principles behind the schemes and their respective advantages and disadvantages. This leads to the adoption of a two dimensional "Volume of Fluid" (VOF) method for the simulation of wave impacts on vertical walls. The VOF method is described in detail, including enhancements to various sections of the algorithm. The "water piston" theory of air pockets is given, together with a scheme to incorporate the effects into the model. The results of a test problem are given which illustrates the ability of the VOF method to simulate free surface flows, and another test case validates the approach to air pocket modelling. Finally a series of comparisons with experimental results of wave impacts is given; these include time series of surface elevations and wall pressures. The results illustrate the difficulty in making direct comparisons with experiment due to the problem of ensuring identical wave conditions and show that, given this constraint, the VOF model is capable of accurate simulation of impact events.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:643135 |
| Date | January 1997 |
| Creators | Chopra, Akash |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/13379 |
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