Non-normality and nonlinearity in thermoacoustic instabilities. (June 2016)

• Record Type: Journal Article
• Authors: Sujith, RI; Juniper, MP; Schmid, PJ
• Is Part Of: International journal of spray and combustion dynamics. Volume 8:Number 2(2016)
• Page Start: 119
• Page End: 146
• Publication Date: 2016-06
• Subjects: Thermoacoustic instability -- non-normality -- nonlinearity -- transient growth -- triggering; Combustion engineering -- Periodicals; Fluid dynamics -- Periodicals; Combustion -- Periodicals; Spraying -- Periodicals; Combustion; Combustion engineering; Fluid dynamics; Spraying; Periodicals; 541.361
• DOI: 10.1177/1756827716651571
• Languages: English
• ISSNs: 1756-8285

Abstract

Analysis of thermoacoustic instabilities were dominated by modal (eigenvalue) analysis for many decades. Recent progress in nonmodal stability analysis allows us to study the problem from a different perspective, by quantitatively describing the short-term behavior of disturbances. The short-term evolution has a bearing on subcritical transition to instability, known popularly as triggering instability in thermoacoustic parlance. We provide a review of the recent developments in the context of triggering instability. A tutorial for nonmodal stability analysis is provided. The applicability of the tools from nonmodal stability analysis are demonstrated with the help of a simple model of a Rjike tube. The article closes with a brief description of how to characterize bifurcations in thermoacoustic systems.