The acoustic equivalence of a mass and heat source
2016 (English)In: 22nd AIAA/CEAS Aeroacoustics Conference, 2016, American Institute of Aeronautics and Astronautics, 2016Conference paper (Refereed)
In combustion systems, unsteady heat release acts as a source term to the acoustic field within the combustor and under the right conditions the energy of the acoustic field can exponentially grow, leading to a combustion instability. An acoustic driver such as a loudspeaker or horn also acts as a source term to the acoustic field and is often modelled as a fluctuating mass source. Considering the similarity of the flame and the acoustic driver to acts as a source to the acoustic field, the question arises if these two types of sources can be interchanged. This contribution investigates that question by considering a 1-D system with mean flow. In the governing equations a mass source term is included which is linearly related to velocity fluctuations. The results are compared with that of a system with a compact heat source. It is found that the two systems are equivalent when there is no mean flow. In the presence of flow, the response of both systems can approximately be the same when special conditions are met.
Place, publisher, year, edition, pages
American Institute of Aeronautics and Astronautics, 2016.
Acoustic fields, Aeroacoustics, Combustion, Loudspeakers, Acoustic drivers, Combustion instabilities, Combustion systems, Governing equations, Heat release, Mass sources, Source terms, Velocity fluctuations, Thermoacoustics
IdentifiersURN: urn:nbn:se:kth:diva-195459ScopusID: 2-s2.0-84982952521ISBN: 9781624103865OAI: oai:DiVA.org:kth-195459DiVA: diva2:1050235
22nd AIAA/CEAS Aeroacoustics Conference, 2016, 30 May 2016 through 1 June 2016
QC 201611282016-11-282016-11-032016-11-28Bibliographically approved