This work is concerned with the modelling of fluid flows on moving domains. The physical problems considered are free surface flows, possibly in the presence of the surface tension phenomena, fluid-rigid body and fluid-structure interaction. The fluid flow considered is governed by the incompressible Navier-Stokes equations. It is modelled by stabilised low order velocity-pressure finite elements. A detailed analysis of time integration strategies is performed leading to the choice of the discrete implicit generalised-α method for the temporal discretisation. The motion of the fluid domain is accounted for by an arbitrary Eulerian-Lagrangian (ALE) strategy. Different mesh update methods are considered. The free surface and the fluid-solid interfaces are modelled carefully, satisfying the necessary conservation properties. These computational ingredients result in fully implicit and strongly coupled sets of nonlinear equations, which are rephrased in a common general framework by decomposing the problems into the fluid, the interface and possibly the solid domains. In order to obtain the exact solution variables, a partitioned Newton-Raphson procedure, based on the exact linearization of the residuals, is developed. Thus, the strong coupling is resolved and optimal convergence can be expected. Finally, a number of two dimensional or axisymmetric numerical examples is presented which demonstrate the robustness and the efficiency of the overall algorithm. The strategy is verified against various reference solutions. The numerical examples include the simulation of the filling of drops, the stretching of liquid bridges, the vortex induced oscillations and the galloping of solid bodies.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:636441 |
| Date | January 2005 |
| Creators | Dettmer, W. G. |
| Publisher | Swansea University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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