Abstract

Noise generation is a consequence of most combustion processes (see: IFRF Handbook Combustion File 176 What are the main sources of noise in combustion systems?). At low levels, it can give rise to complaints from employees or neighbours. At higher levels, there may be difficulties in working safely in a noisy environment, or even a risk of hearing damage.

An extreme form of combustion noise occurs when there is a positive coupling between the flame and the acoustics of the combustion system or some flow instabilities in the fuel or air supplies. These create combustion driven oscillations, also known as resonance or hum.

Although combustion driven oscillations are relatively infrequent, when they do occur, they may cause extreme forms of work place/neighbourhood problems or even lead to risks of structural damage or combustion instability/flame failure. Noise from low frequency combustion oscillations (often at infrasound frequencies) travels long distances with little attenuation.

TOTeM19 aims to present an overview of current problems and activities in the field of combustion noise in industrial plant and gas turbines – particularly combustion oscillations, dealing with topics such as:

• Sources and mechanisms
• Measurement and analysis
• Modelling unsteady combustion systems
• Noise suppression (Passive or Active)
• Practical examples of solutions to problems
• Pulsed combustion for process enhancement

The TOTeM includes several invited overview papers and an interactive poster session.

The objective of TOTeM19 is to:

• Inform participants of current status of our understanding
• Establish IFRF members needs and preoccupations
• Establish what additional guidance on noise that might be included in the IFRF On-line Combustion Handbook

Neil Fricker
Dorridge, UK, January 2002