Imperial College London
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ProfessorSpencerSherwin

Faculty of Engineering, Department of Aeronautics

Head of the Department of Aeronautics
 
 
 
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Contact

 

+44 (0)20 7594 5052s.sherwin Website

 
 
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Location

 

318City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Ekelschot:2017:10.1016/j.compstruc.2016.03.004,
author = {Ekelschot, D and Moxey, D and Sherwin, SJ and Peiro, J},
doi = {10.1016/j.compstruc.2016.03.004},
journal = {Computers and Structures},
pages = {55--69},
title = {A p-adaptation method for compressible flow problems using a goal-based error indicator},
url = {http://dx.doi.org/10.1016/j.compstruc.2016.03.004},
volume = {181},
year = {2017}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - An accurate calculation of aerodynamic force coefficients for a given geometry is of fundamental importance for aircraft design. High-order spectral/hp element methods, which use a discontinuous Galerkin discretisation of the compressible Navier–Stokes equations, are now increasingly being used to improve the accuracy of flow simulations and thus the force coefficients. To reduce error in the calculated force coefficients whilst keeping computational cost minimal, we propose a p-adaptation method where the degree of the approximating polynomial is locally increased in the regions of the flow where low resolution is identified using a goal-based error estimator as follows.Given an objective functional such as the aerodynamic force coefficients, we use control theory to derive an adjoint problem which provides the sensitivity of the functional with respect to changes in the flow variables, and assume that these changes are represented by the local truncation error. In its final form, the goal-based error indicator represents the effect of truncation error on the objective functional, suitably weighted by the adjoint solution. Both flow governing and adjoint equations are solved by the same high-order method, where we allow the degree of the polynomial within an element to vary across the mesh.We initially calculate a steady-state solution to the governing equations using a low polynomial order and use the goal-based error indicator to identify parts of the computational domain that require improved solution accuracy which is achieved by increasing the approximation order. We demonstrate the cost-effectiveness of our method across a range of polynomial orders by considering a number of examples in two- and three-dimensions and in subsonic and transonic flow regimes. Reductions in both the number of degrees of freedom required to resolve the force coefficients to a given error, as well as the computational cost, are both observed in using the p-adaptive technique.
AU  - Ekelschot,D
AU  - Moxey,D
AU  - Sherwin,SJ
AU  - Peiro,J
DO  - 10.1016/j.compstruc.2016.03.004
EP  - 69
PY  - 2017///
SN  - 0045-7949
SP  - 55
TI  - A p-adaptation method for compressible flow problems using a goal-based error indicator
T2  - Computers and Structures
UR  - http://dx.doi.org/10.1016/j.compstruc.2016.03.004
UR  - https://www.sciencedirect.com/science/article/pii/S0045794916300566?via%3Dihub#!
UR  - http://hdl.handle.net/10044/1/30414
VL  - 181
ER  -
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