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LINN, IRONS—POWER LOSSES IN HIGH-SPEED JOURNAL BEARINGS 621D e r iv a t io n o f P o w e r-L oss F o rm u laIn order to demonstrate the interrelationship of the primaryvariables affecting the power loss in bearings, Equation [1 ] wasderived from the test data. The formula is entirely empiricaland it should be noted is based on data which have been madeconsistent within itself. An analysis of the derivation follows:Referring to Fig. 10, log /, plotted against log ZNQ/p atconstant pressure, gives a series of straight-line curves with thebearing size Id as a parameter. These straight lines may be expressedmathematically by an expression of the formwhereNowwhereF ig . 13ZNQ/p V e r s u s f C u r v e s f o r 12 X 1 6 -In . 1 3 0 -D e g JL in in gHenceorFrom the definition of the coefficient of frictionSubstituting Equation [13] in Equation [12]From the master curves of which Figs. 7 and 8 are examples at150 and 600 psi, respectively, the values of /