Identifying sources of thermoacoustic vibrations (rumble) in industrial furnaces and boilers
Industrial gas-fired boilers, furnaces and heaters occasionally suffer low-frequency vibrations generated by dynamic feedback between the burner (or burners) and acoustic modes in adjacent cavities in the main combustion chamber or ductwork. Feedback occurs when pressure pulses associated with acoustic resonances propagate to the burner so that they are in phase with combustion rate fluctuations. When the combustion and acoustic fluctuations become sufficiently phase-synchronized, normal sources of dissipation are insufficient to damp the combined pressure waves, and they can become sufficiently amplified to reduce thermal efficiency, increase emissions, and even cause structural damage. In the literature, such oscillations are referred to as thermoacoustic oscillations or ‘rumble’, and their basic physics have been the subject of numerous investigations for well over a century. Although it occurs relatively infrequently, rumble poses a significant challenge because it is difficult to predict, diagnose, and resolve. The underlying relationships involved are sufficiently complex that it is possible for two apparently identical boilers or furnaces to exhibit completely different rumble tendencies. In this study, we review common sources of rumble and how nonlinear signal analyses, such as bivariate mutual information and transfer entropy, can be used to locate both its sources and impact in boilers, furnaces and heaters.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- DOE Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1560394
- Resource Relation:
- Conference: AFRC Industrial Combustion Symposium - Salt Lake City, Utah, United States of America - 9/17/2018 8:00:00 AM-9/19/2018 8:00:00 AM
- Country of Publication:
- United States
- Language:
- English
Similar Records
An experimental investigation of thermoacoustic instabilities in a premixed swirl-stabilized flame
Nonlinear heat-release/acoustic model for thermoacoustic instability in lean premixed combustors