Effects of Freestream Turbulence on Cavity Tone and Sound Source

<div>Instantaneous isosurfaces of second invariant of velocity tensor gradient <svg height="15.0208pt" id="M172" style="vertical-align:-3.429399pt" version="1.1" viewbox="-0.0498162 -11.5914 61.5833 15.0208" width="61.5833pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="346" vert-adv-y="346"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M474 429L457 433C435 440 389 448 367 448C348 448 323 446 309 443C266 434 195 406 148 366C78 307 23 210 23 101C23 35 55 -12 92 -12C118 -12 146 1 196 35C247 70 311 130 346 173H348L281 -148C268 -211 256 -221 208 -229L191 -232L187 -257L433 -245L437 -219L411 -216C357 -210 350 -205 362 -140L427 207C447 315 461 381 474 429ZM387 387C379 337 363 262 355 236C318 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(a) Cavity flow without freestream turbulence (Tu = 0.0%). (b) Cavity flow with freestream turbulence, Tu = 2.3%.</div>

International Journal of Aerospace Engineering

Effects of Freestream Turbulence on Cavity Tone and Sound Source

Figure 16