Modeling, Numerical Approximation, and Control of Aeroacoustic Noise

This project centers on the modeling and control of high intensity cavity pressure fields generated by adjacent flow fields. Flow-induced acoustic fields in cavities such as wheel wells or bomb bays can have sufficient magnitude (140-170 dB) to produce structural damage if unaccommodated. The basic physical mechanisms which generate the acoustic fields and the utilization of these mechanisms for control design are under investigation.

The adjacent flow fields are inherently nonlinear and are typically modeled by either Navier-Stokes or Euler equations. The acoustic field is inherently compressible and also exhibits nonlinear dynamics at the decibel levels which produce damage. The modeling component focuses on issues concerning the coupling of the fields through unsteady shear layers and the development of boundary conditions which quantify the energy losses measured in experiments. Large scale numerical simulations are being run to determine the accuracy and limitations of the models and to ascertain the open loop dynamics of the system. To facilitate both simulations and control design, it is necessary to develop reduced-order approximation methods. One method under consideration entails the representation of system dynamics through the construction of appropriate POD basis elements. Once this phase is completed, the investigation will focus on the design and implementation of open and closed loop control methods which utilize the reduced-order basis.

CRSC researchers participating in this project include H.T. Banks, D. Bortz, A. Cain and R.C. Smith working in collaboration with scientists at the Boeing Company and at Innovative Technology Applications Company, LLC.


Center for Research in Scientific Computation
Box 8205
North Carolina State University
Raleigh, NC 27695-8205
voice: (919) 515-5289
fax: (919) 515-1636
email: crsc@math.ncsu.edu