简介:The rod-airfoil con痝uration is a benchmark test case for aeroacoustic assessments of vortex-
structure interaction noise. Several industrial devices are arranged in such a way that down-
stream bodies are embedded in 简介:The rod-airfoil con痝uration is a benchmark test case for aeroacoustic assessments of vortex-
structure interaction noise. Several industrial devices are arranged in such a way that down-
stream bodies are embedded in the wake of upstream bodies, such as gas turbines, high lift
devices, helicopters among others. Aeroacoustic predictions usually rely on time dependent
皁w 痚ld information obtained from CFD for the determination of the aeroacoustic sources.
The present work proposes a novel approach for the aeroacoustic prediction of rod-airfoil noise
based on time-resolved PIV experimental data.
The aeroacoustic emission of a NACA0012 airfoil in the Karman wake of a rod is investigated
by means of 2D TR-PIV in combination with beamforming and microphone measurements.
First the time evolving velocity 痚ld around the airfoil is measured using high-speed PIV.
The corresponding pressure 痚ld is then deduced by spatial integration of a Poisson-based
algorithm for quasi-2D incompressible 皁ws. Pressure and velocity computed on speci痗
surfaces around the airfoil constitute the source terms of the implemented Curle's and Ffowcs
Williams-Hawkings's aeroacoustic analogies. The calculated Sound Pressure Level (SPL) is
compared with the measurements obtained by far 痚ld microphones. Velocity visualizations
in the spanwise direction provide qualitative information about the phase coherence of the
vortical impingement along the airfoil span. Parametric studies are performed to evaluate the
e甧ct on the acoustic prediction of the position of the integration surface and the numerical
discretization methods employed.详细>