Skin Friction Reduction Characteristics of Nonsmooth Surfaces Inspired by the Shapes of Barchan Dunes

<table class="table-group" id="tab6"><tr><td><table class="table"><tr><td class="thead-hr" colspan="6"><hr/></td></tr><tr class="thead"><td class="align_left">Source</td><td class="align_center">Sum of squares</td><td class="align_center">DOF</td><td class="align_center">Mean sum of square</td><td class="align_center"><svg height="8.68572pt" id="M82" style="vertical-align:-0.0498209pt" version="1.1" viewbox="-0.0498162 -8.6359 8.02022 8.68572" width="8.02022pt" 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="M584 650H137L131 622C214 614 217 612 200 521L125 127C109 41 101 35 23 28L17 0H288L294 28C201 35 193 42 209 128L242 309H348C440 309 442 300 443 226H471L510 422H482C452 354 449 348 357 348H251L295 575C302 609 304 615 338 615H426C502 615 517 604 526 581C534 560 536 524 537 492L565 494C574 554 583 631 584 650Z" id="g113-71"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="607" vert-adv-y="607"></glyph.data></g></svg> value</td><td class="align_center">Significance level <i>α</i></td></tr><tr><td class="thead-hr" colspan="6"><hr/></td></tr><tr><td class="align_left">Depth</td><td class="align_center">0.00146342</td><td class="align_center">2</td><td class="align_center">0.00073171</td><td class="align_center">19.75</td><td class="align_center">0.05</td></tr><tr><td class="align_left">Angle of repose</td><td class="align_center">0.00050133</td><td class="align_center">2</td><td class="align_center">0.00025066</td><td class="align_center">6.77</td><td class="align_center">0.25</td></tr><tr><td class="align_left">Spacing</td><td class="align_center">0.00154501</td><td class="align_center">2</td><td class="align_center">0.00077250</td><td class="align_center">20.85</td><td class="align_center">0.05</td></tr><tr><td class="align_left">Error</td><td class="align_center">0.00007409</td><td class="align_center">2</td><td class="align_center">0.00003704</td><td class="align_center">—</td><td class="align_center">—</td></tr><tr><td class="align_left" colspan="6"><hr/></td></tr><tr><td class="align_left" rowspan="2">Grand total</td><td class="align_center" rowspan="2">0.00358384</td><td class="align_center" rowspan="2">8</td><td class="align_center"><span style="width: 83.9464ptpx;"><svg height="11.5564pt" id="M83" style="vertical-align:-2.26807pt" version="1.1" viewbox="-0.0498162 -9.28833 83.9464 11.5564" width="83.9464pt" 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="M584 650H137L131 622C214 614 217 612 200 521L125 127C109 41 101 35 23 28L17 0H288L294 28C201 35 193 42 209 128L242 309H348C440 309 442 300 443 226H471L510 422H482C452 354 449 348 357 348H251L295 575C302 609 304 615 338 615H426C502 615 517 604 526 581C534 560 536 524 537 492L565 494C574 554 583 631 584 650Z" id="g113-71"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="607" 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transform="matrix(.013,0,0,-0.013,64.853,0)"><path d="M244 635C114 635 38 519 38 422C38 317 111 240 217 240C236 240 255 244 277 256L345 292C311 140 203 39 59 15L64 -15C89 -15 150 -5 204 17C339 72 440 202 440 386C440 521 368 635 244 635ZM228 602C326 602 352 479 352 390C352 370 351 347 348 324C327 308 293 296 258 296C174 296 124 369 124 458C124 517 152 602 228 602Z" id="g113-58"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="480" vert-adv-y="480"></glyph.data></g></svg></span></td><td class="align_center"> </td></tr><tr><td class="align_center"><span style="width: 77.683ptpx;"><svg height="11.5564pt" id="M85" style="vertical-align:-2.26807pt" version="1.1" viewbox="-0.0498162 -9.28833 77.683 11.5564" width="77.683pt" 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="M584 650H137L131 622C214 614 217 612 200 521L125 127C109 41 101 35 23 28L17 0H288L294 28C201 35 193 42 209 128L242 309H348C440 309 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Variance analysis of numerical simulation test results.

Mathematical Problems in Engineering

tab6

Table 6

Table 6: Skin Friction Reduction Characteristics of Nonsmooth Surfaces Inspired by the Shapes of Barchan Dunes 