Broadband trailing edge noise from a sharp-edged strut

Abstract

This paper presents experimental data concerning the flow and noise generated by a sharp-edged flat plate at low-to-moderate Reynolds number (Reynolds number based on chord of 2.0 × 10(5) to 5.0 × 10(5)). The data are used to evaluate a variety of semi-empirical trailing edge noise prediction methods. All were found to under-predict noise at lower frequencies. Examination of the velocity spectra in the near wake reveals that there are energetic velocity fluctuations at low frequency about the trailing edge. A semi-empirical model of the surface pressure spectrum is derived for predicting the trailing edge noise at low-to-moderate Reynolds number.

Improved Delayed Detached Eddy Simulation modeling and far-field trailing-edge noise estimation of a sharp-edged symmetric strut

“…Figure 5 shows profiles of mean velocity and rms velocity fluctuation measured at a point immediately downstream of the trailing edge of the airfoil [Moreau et al, 2011]. These are compared with predictions made using the RANS and IDDES simulations.…”

“…Further investigations comparing experimental and simulated velocity spectra at identical points in the boundary layer could potentially be used to resolve this issue. Figure 6 shows the noise spectrum measured at a location of y = 585 mm directly above the trailing edge of the plate [Moreau et al, 2011], and predictions made using a number of methods, namely RANS post-processed using RSNM (see also Albarracin et al (2012b)), and IDDES post-processed using RSNM and FWH. Note that the RANS RSNM results differ slightly from those shown in Albarracin et al (2012b).…”

“…Its leading edge is semi-circular and the trailing edge is a symmetric wedge shape with an included angle of 12q. Experimental noise and flow-field measurements for this geometry have been presented by Moreau et al (2011).…”

“…The simulated data were compared with the experimental data of Moreau et al (2011). The simulated geometry and flow conditions were purposefully matched to those of the experiment, which consisted of a physical rig set up in an anechoic wind tunnel.…”

“…Experimental data were collected using hot-wires and microphones. The experimental setup together with the flow and noise measurements are detailed in Moreau et al (2011) and thus are not repeated here. Figure 3a shows the mean velocity field in the vicinity of the plate for the RANS solution.…”