Analysis of Acoustic Cavitation Surge in a Rocket  Engine Turbopump

<table>(a) Comparison of frequency between experimental results and analytical results (<svg height="12.0125" id="M95" style="vertical-align:-3.3525pt" version="1.1" viewbox="0 0 19.25 12.0125" width="19.25" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,-0,0,-.012,10.912,11.863)"><path d="M627 18l-10 -26q-79 6 -116 27t-69 76q-41 71 -71 138q-13 29 -27.5 39t-42.5 10h-46l-27 -145q-13 -74 -2.5 -88.5t78.5 -20.5l-6 -28h-271l5 28q66 6 82.5 21.5t30.5 87.5l71 387q12 66 2 78.5t-77 19.5l8 28h233q102 0 147 -29q65 -43 65 -129q0 -69 -45.5 -117
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</svg>) using CFD-calculated <svg height="11.175" id="M96" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 13.3125 11.175" width="13.3125" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> and <svg height="11.175" id="M97" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 17.475 11.175" width="17.475" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg><i>. </i>(b) Analytical results of damping rate (<svg height="11.925" id="M98" style="vertical-align:-3.27605pt" version="1.1" viewbox="0 0 16.7875 11.925" width="16.7875" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>) using <svg height="18.3125" id="M99" style="vertical-align:-5.73166pt" version="1.1" viewbox="0 0 35.362499 18.3125" width="35.362499" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>, CFD-calculated <svg height="11.175" id="M100" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 13.3125 11.175" width="13.3125" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,11.113)"><path d="M764 650l-7 -26q-61 -10 -91.5 -22.5t-76.5 -48.5l-235 -184q104 -152 208 -276q31 -37 54.5 -48.5t68.5 -16.5l-7 -28h-156q-138 170 -213 284q-19 29 -33.5 35t-33.5 -7l-29 -173q-15 -75 -5.5 -90.5t74.5 -20.5l-5 -28h-260l7 28q58 5 74 21.5t30 89.5l70 378
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</svg> and <svg height="11.175" id="M101" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 17.475 11.175" width="17.475" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg></table>

International Journal of Rotating Machinery

Analysis of Acoustic Cavitation Surge in a Rocket Engine Turbopump

Figure 9