Analysis of Fluid Systems: Stability, Receptivity, Sensitivity
2014 (English)In: Applied Mechanics Review, ISSN 0003-6900, E-ISSN 1088-8535, Vol. 66, no 2, 024803- p.Article, review/survey (Refereed) Published
This article presents techniques for the analysis of fluid systems. It adopts an optimization-based point of view, formulating common concepts such as stability and receptivity in terms of a cost functional to be optimized subject to constraints given by the governing equations. This approach differs significantly from eigenvalue-based methods that cover the time-asymptotic limit for stability problems or the resonant limit for receptivity problems. Formal substitution of the solution operator for linear time-invariant systems results in the matrix exponential norm and the resolvent norm as measures to assess the optimal response to initial conditions or external harmonic forcing. The optimization-based approach can be extended by introducing adjoint variables that enforce governing equations and constraints. This step allows the analysis of far more general fluid systems, such as time-varying and nonlinear flows, and the investigation of wavemaker regions, structural sensitivities, and passive control strategies.
Place, publisher, year, edition, pages
2014. Vol. 66, no 2, 024803- p.
Base-Flow Variation, Global Instabilities, Boundary-Layer, Cross-Flow, Cylinder, Equations
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-146577DOI: 10.1115/1.4026375ISI: 000335815800004ScopusID: 2-s2.0-84896919043OAI: oai:DiVA.org:kth-146577DiVA: diva2:724628
QC 201406132014-06-132014-06-122014-06-13Bibliographically approved