Theoretical and Experimental Study on the Transient Time-Frequency Characteristics of the Bending-Torsional Coupling Motions of a Rub-Impact Dual-Rotor System

<div>Transient time-frequency waterfall curves of the bending and torsional motions of the rotor system for <svg height="9.25658pt" id="M115" style="vertical-align:-3.295671pt" version="1.1" viewbox="-0.0498162 -5.96091 22.0146 9.25658" width="22.0146pt" 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="M615 290C615 392 563 448 529 448C511 448 491 441 484 434L483 425C518 400 546 349 546 273C546 158 504 46 417 46C381 46 356 77 356 142C356 184 380 293 392 334L387 340L307 323C305 288 296 228 287 188C265 94 221 52 180 52C144 52 112 89 112 171C112 278 164 372 241 430L226 454C106 394 23 288 23 155C23 40 79 -12 139 -12C184 -12 245 32 285 85C292 31 322 -12 376 -12C423 -12 470 18 501 45C570 104 615 184 615 290Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.969,3.132)"><path d="M244 0V30C178 35 170 41 170 107V710C136 697 72 680 18 675V647C83 642 89 639 89 572V107C89 43 80 35 16 30V0H244Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,10.335,3.132)"><path d="M262 451C169 451 38 375 38 210C38 98 121 -12 261 -12C360 -12 481 64 481 227C481 351 386 451 262 451ZM249 414C337 414 385 320 385 204C385 70 333 25 272 25C189 25 134 117 134 241C134 355 189 414 249 414Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,14.894,3.132)"><path d="M708 439H523V409C587 401 594 395 581 344C562 272 534 184 513 118H511C468 225 428 330 391 434H361C318 317 283 217 244 121H242C218 196 193 273 170 349C157 394 160 401 220 409V439H10V409C60 403 67 394 86 343C127 224 165 109 201 -10H233C273 101 314 199 353 299C393 195 432 99 475 -10H507C554 126 596 251 627 334C648 390 657 401 708 409V439Z"></path></g></svg> = 1800 rad/s. (a) Bending motion and (b) torsional motion.</div>

Shock and Vibration

fig16

Figure 16

Figure 16: Theoretical and Experimental Study on the Transient Time-Frequency Characteristics of the Bending-Torsional Coupling Motions of a Rub-Impact Dual-Rotor System 

Figure 16 | Theoretical and Experimental Study on the Transient Time-Frequency Characteristics of the Bending-Torsional Coupling Motions of a Rub-Impact Dual-Rotor System 