Skip to Main content Skip to Navigation
Journal articles

Open-loop control of cavity noise using Proper Orthogonal Decomposition reduced-order model

Abstract : Flow over open cavities is mainly governed by a feedback mechanism due to the interaction of shear layer instabilities and acoustic forcing propagating upstream in the cavity. This phenomenon is known to lead to resonant tones that can reach 180 dB in the far-field and may cause structural fatigue issues and annoying noise emission. This paper concerns the use of optimal control theory for reducing the noise level emitted by the cavity. Boundary control is introduced at the cavity upstream corner as a normal velocity component. Model-based optimal control of cavity noise involves multiple simulations of the compressible Navier–Stokes equations and its adjoint, which makes it a computationally expensive optimization approach. To reduce the computational costs, we propose to use a reduced-order model (ROM) based on Proper Orthogonal Decomposition (POD) as a surrogate model of the forward simulation. For that, a control input separation method is first used to introduce explicitly the control effect in the model. Then, an accurate and robust POD ROM is derived by using an optimization-based identification procedure and generalized POD modes, respectively. Since the POD modes describe only velocities and speed of sound, we minimize a noise-related cost functional characteristic of the total enthalpy unsteadiness. After optimizing the control function with the reduced-order model, we verify the optimality of the solution using the original, high-fidelity model. A maximum noise reduction of 4.7 dB is reached in the cavity and up to 16 dB at the far-field.
Complete list of metadata

Cited literature [37 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-01813487
Contributor : Open Archive Toulouse Archive Ouverte (oatao) Connect in order to contact the contributor
Submitted on : Tuesday, June 12, 2018 - 2:03:33 PM
Last modification on : Wednesday, November 3, 2021 - 6:42:43 AM
Long-term archiving on: : Friday, September 14, 2018 - 12:38:48 AM

File

Nagarajan_20149.pdf
Files produced by the author(s)

Identifiers

Citation

Kaushik Kumar Nagarajan, Sintu Singha, Laurent Cordier, Christophe Airiau. Open-loop control of cavity noise using Proper Orthogonal Decomposition reduced-order model. Computers and Fluids, Elsevier, 2018, 160, pp.1-13. ⟨10.1016/j.compfluid.2017.10.019⟩. ⟨hal-01813487⟩

Share

Metrics

Les métriques sont temporairement indisponibles