Large Eddy Simulation of the Interaction of Homogeneous Turbulence with a Flat-Plate Cascade

Abstract

My thanks are due to Mr. Mohammad Elyyan and my daughter Noura for their help in the presentation and Tecplot. I would like to thank the Department of Engineering Science and Mechanics for supporting me financially through GTAs. My gratitude is due to the Egyptian embassy for supporting me financially throughout my stay in the USA. v xiv List of Tables 3.1 The a m coefficients of fourth-order Runge-Kutta scheme [54]. .. .. .. . 3.2 The b m coefficients of fourth-order Runge-Kutta scheme [54]. .. .. .. .

Numerical Predictions of Turbulence/Cascade-Interaction Noise Using Computational Aeroacoustics with a Stochastic Model

“…As proposed by Kraichnan and also adopted in Ref. [29], it is based on a Fourier-mode decomposition of the incoming turbulent wake modeled by an HIT (Homogeneous Isotropic Turbulence) energy spectrum, but restricted here to the upwash velocity component (normal to the airfoil assimilated to a flat plate) by analogy with Amiet's theory. Such an approach aims to reproduce the statistical energy of prescribed TKE spectrum in the frequency domain without trying to capture any space-time correlation scales, which is different to time-domain RPM (Random-Particule Mesh) methods extensively used by Ewert 30 .…”

Experimental and Numerical Investigation of Turbulence-Airfoil Noise Reduction Using Wavy Edges

“…45 As done in ref. [19], it is based on a Fourier-modes decomposition of the incoming turbulent wake modeled as homogeneous isotropic turbulence (HIT) energy spectrum. In the present study, only the upwash velocity component (normal to the airfoil assimilated as a flat plate) is considered with a spatial distribution over streamwise and spanwise wavenumbers, as done in Amiet's theory 4,5 (Fig.…”

“…Dieste and Gabard 17,18 also use this kind of stochastic model to simulate the turbulent wake / flat plate interaction. Salem-Said 19 interests in the interaction between a homogeneous turbulence with a flat plate cascade using LES and a Fourier-mode decomposition of a prescribed kinetic energy spectrum to synthesize the turbulent inflow. [20][21][22] In the European project FLOCON, two different numerical methods have been proposed by Onera to compute turbulence-airfoil interaction noise.…”

Numerical Predictions of Turbulence-Cascade Interaction Noise Using CAA with a Stochastic Model

“…The proposed stochastic model is the simplest and is similar to Kraichnan's theory [28]. As proposed by Kraichnan and also adopted in [29], it is based on a Fouriermode decomposition of the incoming turbulent wake modeled by a homogeneous-isotropic-turbulence (HIT) energy spectrum, but restricted here to the upwash-velocity component (normal to the airfoil assimilated to a flat plate) by analogy with Amiet's [1] theory. Such an approach aims to reproduce the statistical energy of the prescribed TKE spectrum in the frequency domain without trying to capture any space-time correlation scales, which is different to timedomain random-particle-mesh (RPM) methods extensively used by Ewert [30].…”