Sound reflection at an open end of a circular duct exhausting hot gas
2008 (English)In: Noise Control Engineering Journal, ISSN 0736-2501, Vol. 56, no 2, 107-114 p.Article in journal (Refereed) Published
Sound reflection from hot flow duct openings is a classical problem in acoustics. In practice this is important for effective modelling and prediction off noise radiation from engine exhaust systems, burner pipelines, exhaust nozzles etc. Despite several experimental and theoretical investigations in the field, there is still limited experimental data available to validate the existing theory. In the present study, experimental investigations of plane acoustic wave reflections at duct openings where a hot jet flows into relatively cold surrounding media have been carried out. Heated air with well determined and homogenous chemical consistency along the duct axis was used as a testing media inside the duct during the experiments. The studied jet temperatures exhausting from the pipe ranged from room temperature up to 500 degrees C. The standard two-microphone technique was applied to determine the reflection properties at the duct opening. The experimental results for the reflection coefficient magnitude and phase have been compared with Munt's theory and good correlation was found. This result is a first experimental validation of the theory for hot flow conditions.
Place, publisher, year, edition, pages
2008. Vol. 56, no 2, 107-114 p.
Acoustic variables control; Acoustic waves; Acoustics; Environmental engineering; Exhaust systems (engine); Photoacoustic effect; Pipelines; Reflection; Standards; Well testing
Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-19427DOI: 10.3397/1.2898681ISI: 000256460000002OAI: oai:DiVA.org:kth-19427DiVA: diva2:337598
QC 201008062010-08-062010-08-062010-08-09Bibliographically approved