Mixed and Fluid Film Lubrication Characteristics of Worn Journal Bearings

<table>Effect of surface roughness <i>σ</i>/<i>C</i> on frictional coefficient <i>fR</i>/<i>C</i> and side leakage flow rate <svg height="19.9375" id="M144" style="vertical-align:-3.39066pt" version="1.1" viewbox="0 0 18.262501 19.9375" width="18.262501" 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,-.012,13.113,19.725)"><path d="M352 391q0 -31 -27 -44q-14 -7 -24 6q-39 48 -84 48q-23 0 -39.5 -15t-16.5 -40q0 -43 73 -90q49 -32 70 -58t21 -57q0 -58 -62 -105.5t-129 -47.5q-40 0 -75.5 25t-35.5 52q0 28 32 46q7 4 15 3t11 -6q19 -31 48.5 -50.5t54.5 -19.5q34 0 54 19.5t20 42.5q0 43 -65 81
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</svg> in terms of Sommerfeld number <svg height="15.6875" id="M145" style="vertical-align:-3.39066pt" version="1.1" viewbox="0 0 14.475 15.6875" width="14.475" 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,-.012,8.225,15.475)"><path d="M445 282q0 -64 -27.5 -125t-80.5 -104q-80 -65 -168 -65q-73 0 -109.5 46.5t-36.5 116.5q0 92 46.5 163t119.5 104q66 30 108 30q67 0 107.5 -43.5t40.5 -122.5zM355 280q0 62 -26.5 94.5t-64.5 32.5q-26 0 -44 -8q-39 -18 -74 -82t-35 -163q0 -57 25.5 -90.5t70.5 -33.5
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</svg> (no dent and <svg height="20.700001" id="M146" style="vertical-align:-3.39066pt" version="1.1" viewbox="0 0 19.075001 20.700001" width="19.075001" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(1.25,0,0,-1.25,90,90)">
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<g transform="matrix(.017,0,0,-.017,.062,16.413)"><path d="M494 514l-10 -15q-56 76 -106.5 117t-110.5 41q-45 0 -45 -30q0 -28 109 -152q59 -68 86 -118.5t27 -107.5q0 -62 -29.5 -119.5t-86.5 -96.5q-64 -45 -138 -45q-76 0 -121.5 53t-45.5 136q0 74 40.5 135t98.5 95q43 26 87 42q-40 59 -57.5 92t-17.5 62q0 46 39 77.5
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<g transform="matrix(.012,0,0,-.012,8.85,20.5)"><path d="M445 282q0 -64 -27.5 -125t-80.5 -104q-80 -65 -168 -65q-73 0 -109.5 46.5t-36.5 116.5q0 92 46.5 163t119.5 104q66 30 108 30q67 0 107.5 -43.5t40.5 -122.5zM355 280q0 62 -26.5 94.5t-64.5 32.5q-26 0 -44 -8q-39 -18 -74 -82t-35 -163q0 -57 25.5 -90.5t70.5 -33.5
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</svg>= 0.5).</table>

Advances in Tribology

fig9

Figure 9

Figure 9: Mixed and Fluid Film Lubrication Characteristics of Worn Journal Bearings 