An assessment of inter-grid transformation for a whole aircraft

Rampurawala, Abdul Moosa (2002) An assessment of inter-grid transformation for a whole aircraft. MSc(R) thesis, University of Glasgow.

Abstract

As modern military aircraft become lighter, faster and more maneuverable, the consideration of aeroelastic effects during the design process can provide significant benefits. Computational aeroelasticity provides an attractive alternative to wind tunnel testing of flexible models in terms of accurately predicting and simulating the various linear and non-linear phenomena in a cost effective way. Computational Structural Dynamic (CSD) and Computational Fluid Dynamic (CFD) codes have reached a level of development where they can accurately analyse the structural and fluid behaviour. Aeroelastic simulation of individual components of an aircraft is now commonly done but problems arise when simulating a whole aircraft configuration. This is because the CSD solver calculates the elastic response' of the aircraft on a structural grid which usually does not coincide with the CFD surface grid and hence a scheme is required to transfer displacement and force values between the CSD and CFD grids. The various aerodynamic surface patches are driven by different structural components which may require different transformation methods. For example a fuselage, if modelled as a 1-dimensional beam, would require a different transformation technique than the wings which are modelled as 2-dimensional plates. To address this, a modified version of the Constant Volume Tetrahedron (CVT) transformation scheme is proposed for 1-dimensional structural grids. A tagging procedure is used where the fluid grid nodes are identified as being driven by 1 or 2-dimensional structural components and then the appropriate version of the transformation scheme is applied. The other difficulty is that the component interfaces in the fluid grid need to match up properly for the simulation to be successful. To overcome this a weighting method has been developed which forces the grid points at the component interfaces of the fluid grid to match up correctly by averaging the transformation within a predefined hierarchy. In the current work, this methodology has been demonstrated on a generic F16 aircraft configuration. The robustness of the transformation technique is evaluated by using a number of structural models to drive the fluid surface motions.

• Item Type: Thesis (MSc(R))
• Qualification Level: Masters
• Additional Information: Cover Title: Assessment of inter-grid transformation for complete aircraft aeroelastic analysis.
• Keywords: Aerospace engineering
• Colleges/Schools: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity
• Supervisor's Name: Badcock, Dr. Ken
• Date of Award: 2002
• Depositing User: Enlighten Team
• Unique ID: glathesis:2002-71248
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 10 May 2019 10:49
• Last Modified: 08 Aug 2022 08:19
• Thesis DOI: 10.5525/gla.thesis.71248
• URI: https://theses.gla.ac.uk/id/eprint/71248