Development of a Trailing-Edge Noise Prediction Method using the Non-Linear Disturbance Equations

Open Access
Author:
Christiansen, Monica Danielle
Graduate Program:
Aerospace Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
June 07, 2011
Committee Members:
  • Philip John Morris, Thesis Advisor
  • Kenneth Steven Brentner, Thesis Advisor
Keywords:
  • trailing edge noise
  • computational aeroacoustics
  • non-linear disturbance equations
  • wind turbine noise
Abstract:
Currently, the methods available for wind turbine noise prediction are either based on empirical data or require unrealistic computational costs. Although these methods are very valuable, a computationally efficient tool that is based on first principles is needed. The present research proposes a hybrid computational aeroacoustics approach for predicting turbulent-boundary-layer, trailing-edge (TBL-TE) noise. TBL-TE is of interest because it is a dominant source in the total broadband spectrum of wind turbine aerodynamic noise. The proposed method solves the Non-Linear Disturbance Equations (NLDE) for the unsteady flow field in the vicinity of the airfoil trailing edge. Then the noise at a location in far-field location is found by passing the NLDE solution to the aeroacoustics propagation code, PSU-WOPWOP. In this thesis, recent progress made with the development of the NLDE flow solver, TANDEM (Turbulence And Noise using the Disturbance Equation Method) is presented. Test cases are shown to validate the code. Finally, an assessment of the NLDE performance in wall bounded and trailing edge flows is discussed.