Effect of Wing-Wing Interaction on the Propulsive Performance of Two Flapping Wings at Biplane Configuration

<div>The vortex contours of the biplane counter-flapping wing with <svg height="11.7782pt" id="M142" style="vertical-align:-3.42938pt" version="1.1" viewbox="-0.0498162 -8.34882 53.0323 11.7782" width="53.0323pt" 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="M556 393C556 426 537 448 514 448C496 448 478 435 471 420C468 414 462 401 466 394C473 382 480 368 480 346C480 268 392 143 338 67H336C329 163 319 253 309 330S286 448 254 448C215 448 160 383 127 337L143 311C167 344 200 373 208 373S222 365 229 320C246 214 264 66 268 -20C219 -83 131 -171 17 -239L25 -261L137 -235C248 -110 273 -79 335 8C384 77 481 215 520 287C544 332 556 363 556 393Z" id="g113-122"></path></g><g transform="matrix(.0091,0,0,-0.0091,6.942,3.132)"><path d="M357 391C357 416 325 451 270 451C241 451 179 431 146 400C109 365 97 334 97 307C97 248 143 213 196 180C250 146 261 123 261 101C261 75 237 40 190 40C153 40 110 72 86 109C81 116 68 119 55 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Applied Bionics and Biomechanics

fig12

Figure 12

Figure 12: Effect of Wing-Wing Interaction on the Propulsive Performance of Two Flapping Wings at Biplane Configuration 