Imperial College London
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Dr Shahid Mughal

Faculty of Natural Sciences, Department of Mathematics

Lecturer in Applied Mathematics
 
 
 
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Contact

 

+44 (0)20 7594 2648s.mughal Website

 
 
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Location

 

734Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@inbook{Raposo:2019,
author = {Raposo, H and Mughal, M and Ashworth, R},
booktitle = {ERCOFTAC Bulletin 118},
editor = {Marek},
pages = {25--30},
publisher = {www.ercoftac.org},
title = {Uncertainty Quantification of Acoustic Receptivity with an Adjoint Linear Navier-Stokes Approach},
url = {https://drive.google.com/open?id=1Z-Z5dMCB6Pqbrp31vd04AB6V7qZb7VnF},
year = {2019}
}
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RIS format (EndNote, RefMan)

TY  - CHAP
AB  - Receptivity remains one of the key challenges towards holistic models of boundary layer transition and amplitude-based transition criteria. In this paper we briefly describe a high-fidelity acoustic receptivity model built upon the compressible time-harmonic linearised Navier-Stokes equations which is believed to be generalizable to complex geometries and could potentially be used in industrial applications. We demonstrate how the adjoint methodology is essential to rapidly quantify the effects of uncertainty in distributed random roughness over the amplitude of Tollmien-Schlichting waves. Three models of the acoustic boundary layer signature (BLAS) based on the linearised unsteady boundary layer equations (LUBLE) and the linear stability equations (LSE) are indirectly compared against each other and against finite-Reynolds number theory (FRNT) through quantification of the efficiency function. The LUBLE are shown to be an adequate choice of model through a large range of incidence angles at M∞ = 0.9 (θ < 140) but they fail to model a weakening of the BLAS at larger incidences, i.e. for near-upstream propagating waves. In turn, the inviscid-LSE model is qualitatively correct but over-predicts receptivity at finite-Strouhal numbers. Lastly, the viscous-LSE model is in remarkable agreement with FRNT, thus showing that non-parallel flow effects for two-dimensional disturbances convecting over a flat plate geometry remain weak up to near-sonic flow conditions.
AU  - Raposo,H
AU  - Mughal,M
AU  - Ashworth,R
EP  - 30
PB  - www.ercoftac.org
PY  - 2019///
SP  - 25
TI  - Uncertainty Quantification of Acoustic Receptivity with an Adjoint Linear Navier-Stokes Approach
T1  - ERCOFTAC Bulletin 118
UR  - https://drive.google.com/open?id=1Z-Z5dMCB6Pqbrp31vd04AB6V7qZb7VnF
ER  -
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