The reduction of drag on commercial aircraft is an active field of study especially with environmental pressures to reduce the carbon emissions associated with climate change. To this end, the AEROMEMS-II project was commissioned by the EU with a view to investigate methods for reducing drag by using MEMS devices for controlling separation. One method for investigating flow control devices is to use the field of Computational Fluid Dynamics (CFD) to simulate the flow interactions produced in flow control applications and assess their effect. Simulating such flows can be computationally expensive so a number of methods have been investigated here to assess their use in flow control simulation applications. The first of these is the Immersed Boundary Method (IBM) which allows complex geometries to be simulated using simple cartesian grid CFD codes. IBMs are found to reduce requirements whilst maintaining flow resolution and accuracy. Next is the use of turbulence modelling with wall functions to reduce the need for fine grids near any solid surfaces. This method is found to work well and can allow the grid spacing near the wall to be 100 times coarser than with no wall functions applied. Finally, Detached Eddy Simulation (DES) has been considered as a method for allowing unsteady flow control structures to be simulated without being damped by conventional turbulence modelling. Each of these methods is presented, implemented and validated against known flow cases to assess their abilities fully. All three methods have then been applied together to a known experimental turbulent flow-control set-up at the University of Lille (fellow partners in the AEROMEMS-II project) in order to assess the feasibility of using all of these methods together to simulate flow control. All three of these methods are seen to work well together although not always with the same effect.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:487836 |
| Date | January 2008 |
| Creators | Preece, Adam |
| Publisher | University of Warwick |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://wrap.warwick.ac.uk/94093/ |
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