Numerical and analytical investigation of the indirect combustion noise in a nozzle

Matthieu Leyko (1) , Franck Nicoud (2) , Stéphane Moreau (3) , Thierry Poinsot (4)

1 SNECMA Villaroche [Moissy-Cramayel]
2 I3M - Institut de Mathématiques et de Modélisation de Montpellier
3 GAUS
4 IMFT - Institut de mécanique des fluides de Toulouse

Analytical and numerical assessments of the indirect noise generated through a nozzle are presented. The configuration corresponds to an experimental setup operated at DLR by Bake et al. (2008) where an entropy wave is generated upstream of the nozzle by means of an electrical heating device. Both 3-D and 2-D axisymmetric simulations are performed to demonstrate that the experiment is mostly driven by linear acoustic phenomena, including pressure wave reflection at the outlet and entropy-to-acoustic conversion in the accelerated regions. Results show that the acoustic impedance downstream of the nozzle must be accounted for appropriately in order to recover the experimental pressure signal. A good agreement is also obtained with a purely analytical assessment based on the Marble and Candel compact nozzle approximation.

Mots clés: Combustion; Thermoacoustic; Indirect combustion noise; Numerical simulations; ENTROPY FLUCTUATIONS; SHOCK-WAVE

Domaines: Acoustique [physics.class-ph]; Acoustique [physics.class-ph]; Milieux fluides et réactifs

Matthieu Leyko, Franck Nicoud, Stéphane Moreau, Thierry Poinsot. Numerical and analytical investigation of the indirect combustion noise in a nozzle. Comptes rendus de l’Académie des sciences. Série IIb, Mécanique, 2009, 337 (6-7), pp.415-425. ⟨10.1016/j.crme.2009.06.025⟩. ⟨hal-00803811⟩