Further Development and Initial Validation of Innovative DES-Based Approaches for the Prediction of Jet Noise Installation Effects

Abstract

Further development and validation of an innovative DES-based methodology for the prediction of jet noise from installed configurations is presented. A Grey-Area improved Delayed Detached-Eddy Simulation (DDES) model has been implemented in an industrial solver and validated for a static single-stream jet. The measured far-field sound directivity was predicted to within 2 dB and frequencies up to around St = 2 to 3 were resolved on a grid of 15.4M cells. To address the key problem of defining a suitable location of the data surface for Ffowcs Williams & Hawkings (FWH) far-field integration, a sensor function based on a statistical evaluation of the vorticity magnitude is proposed. This is applied to a complex installed jet/wing configuration, for which predicted far-field noise levels are shown. A strong increase in noise due to the presence of the wing of up to 18 dB in the forward arc is reported. This interaction noise becomes stronger and shifts to higher frequencies when the wing is moved closer to the jet.

Large Eddy Simulations of Isolated and Installed Jet Noise using the High-Order Discontinuous Galerkin Method

“…[16,17,21]. Alternatively, the integration surface can be left open at the downstream end [19,22,31,40,67]. In this work, we use the latter option.…”

“…Most studies of jet noise to date have used a finite volume or a finite difference method to discretize the governing equations in space, see e.g. [13][14][15][16][17][18][19][20][21][22][23] and [24][25][26][27][28][29][30][31]. In some of these studies, a subgrid-scale model is used to account for the unresolved turbulent scales [14, 16-19, 21-23, 31].…”

Aeroacoustic Analysis of a Closely Installed Chevron Nozzle Jet using the High-Order Discontinuous Galerkin Method

“…Instead, finite volume and finite difference methods are predominantly used, see e.g. [28][29][30][31][32][33][34][35][36][37][38][39][40][41] and [42][43][44][45][46][47]. Together with several review papers [48][49][50], these studies demonstrate the tremendous progress that has been made in numerical jet noise predictions based on scale resolving simulations over the past decades.…”

“…Several solutions to this problem have been proposed in the literature, including the method of end-caps [28], the pressure formulation of the Ffowcs Williams -Hawkings equation [64], and the additional surface terms proposed by Rahier et al [66]. Alternatively, the integration surface can be left open at the downstream end [26,35,38,40,67]. The last option can lead to poor predictions of the lowest frequencies [28,65].…”