Imperial College London
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ProfessorJonathanMorrison

Faculty of Engineering, Department of Aeronautics

Professor of Experimental Fluid Mechanics
 
 
 
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Contact

 

+44 (0)20 7594 5067j.morrison Website

 
 
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Location

 

CAGB315City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Brackston:2016:10.1007/s00348-016-2243-4,
author = {Brackston, RD and Wynn, A and Morrison, JF},
doi = {10.1007/s00348-016-2243-4},
journal = {Experiments in Fluids},
title = {Extremum seeking to control the amplitude and frequency of a pulsed jet for bluff body drag reduction},
url = {http://dx.doi.org/10.1007/s00348-016-2243-4},
volume = {57},
year = {2016}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Feedback control of fluid flows presents a challenging problem due to nonlinear dynamics and unknown optimal operating conditions. Extremum seeking control presents a suitable method for many flow control situations but involves its own challenges. In this paper we provide a brief analysis of the extremum seeking method, with attention to modifications that we find to be advantageous. In particular, we present an adaptation for optimisation ofthe frequency of a harmonic input signal, a common scenario for open-loop flow control systems. We then present results from the experimental implementation of our modified method to the open-loop control system of Oxlade et al (2015, J. Fluid Mech., vol. 770), an axisymmetric bluff bodywake, forced by a pulsed jet. We find that the system is able to achieve optimal operating conditions in both the amplitude and frequency of the harmonic input signal, and is able to largely reject the disturbances arising from measurements of a highly turbulent flow. We finally show the ability of the extremum seeking system to adapt to changing conditions.
AU  - Brackston,RD
AU  - Wynn,A
AU  - Morrison,JF
DO  - 10.1007/s00348-016-2243-4
PY  - 2016///
SN  - 1432-1114
TI  - Extremum seeking to control the amplitude and frequency of a pulsed jet for bluff body drag reduction
T2  - Experiments in Fluids
UR  - http://dx.doi.org/10.1007/s00348-016-2243-4
UR  - http://hdl.handle.net/10044/1/39924
VL  - 57
ER  -
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