CaltechAUTHORS
  A Caltech Library Service

Optimal control of circular cylinder wakes using long control horizons

Flinois, Thibault L. B. and Colonius, Tim (2015) Optimal control of circular cylinder wakes using long control horizons. Physics of Fluids, 27 (8). Art. No. 087105. ISSN 1070-6631. https://resolver.caltech.edu/CaltechAUTHORS:20150924-105657541

[img] PDF - Published Version
See Usage Policy.

1347Kb
[img] PDF - Submitted Version
See Usage Policy.

748Kb

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20150924-105657541

Abstract

The classical problem of suppressing vortex shedding in the wake of a circular cylinder by using body rotation is revisited in an adjoint-based optimal control framework. The cylinder’s unsteady and fully unconstrained rotation rate is optimized at Reynolds numbers between 75 and 200 and over horizons that are longer than in previous studies, where they are typically of the order of a vortex shedding period or shorter. In the best configuration, the drag is reduced by 19%, the vortex shedding is effectively suppressed, and this low drag state is maintained with minimal cylinder rotation after transients. Unlike open-loop control, the optimal control is shown to maintain a specific phase relationship between the actuation and the shedding in order to stabilize the wake. A comparison is also given between the performance of optimizations for different Reynolds numbers, cost functions, and horizon lengths. It is shown that the long horizons used are necessary in order to stabilize the vortex shedding efficiently.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1063/1.4928896DOIArticle
http://scitation.aip.org/content/aip/journal/pof2/27/8/10.1063/1.4928896PublisherArticle
http://arxiv.org/abs/1504.03949arXivDiscussion Paper
ORCID:
AuthorORCID
Colonius, Tim0000-0003-0326-3909
Additional Information:© 2015 AIP Publishing LLC. Received 2 February 2015; accepted 6 August 2015; published online 25 August 2015.
Issue or Number:8
Record Number:CaltechAUTHORS:20150924-105657541
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20150924-105657541
Official Citation:Optimal control of circular cylinder wakes using long control horizons Flinois, Thibault L. B. and Colonius, Tim, Physics of Fluids, 27, 087105 (2015), DOI:http://dx.doi.org/10.1063/1.4928896
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:60482
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:24 Sep 2015 21:00
Last Modified:03 Oct 2019 08:57

Repository Staff Only: item control page