Free Vibration Analysis of Rotating Pretwisted Functionally Graded Sandwich Blades

<div>A Campbell diagram of the FG sandwich blade (<span class="nowrap"><svg height="12.7569pt" id="M301" style="vertical-align:-0.2063999pt" version="1.1" viewbox="-0.0498162 -12.5505 24.7964 12.7569" width="24.7964pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><rect height="0.65243" width="3.51009" x="0" y="-11.8482"></rect><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M238 681C243 705 239 712 230 712C217 712 156 682 75 674L70 648H105C148 648 153 641 144 598L39 110C18 11 35 -12 55 -12C90 -12 166 36 221 103L205 125C174 93 130 65 118 65C112 65 108 68 114 96L238 681Z" id="g113-109"></path></g><g transform="matrix(.013,0,0,-0.013,7.142,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z" id="g117-34"></path></g><g transform="matrix(.013,0,0,-0.013,18.405,0)"><path d="M285 378C315 398 338 416 353 432C373 451 384 474 384 503C384 579 325 635 236 635H235C182 635 136 610 108 579L65 516L85 496C110 533 150 575 205 575C258 575 300 543 300 481C300 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International Journal of Aerospace Engineering

fig12

Figure 12

Figure 12: Free Vibration Analysis of Rotating Pretwisted Functionally Graded Sandwich Blades 