TAILIEUCHUNG - Ebook Fundamentals of fluid film lubrication (second edition): Part 2
(BQ) Part 2 book "Fundamentals of fluid film lubrication" has contents: Hydrodynamic journal bearings - Analytical solutions; hydrodynamic journal bearings - Numerical solutions; hydrodynamic squeeze film bearings; hydrostatic lubrication, gas lubricated thrust bearings, hydrodynamic lubrication of nonconformal surfaces | Chapter 10 Hydrodynamic Journal Bearings - Analytical Solutions Symbols A h c e ft ftm TVa P Pm p Pm 9 q^ <7^, Q r fa ?"b integration constant width of bearing, m radial clearance of journal bearing, m eccentricity of journal bearing, m film thickness, m film thickness where dp/c%<^ =1 0, m angular velocity, rpm dimensionless pressure dimensionless pressure where pressure, N/m^ pressure where dp/<%) = 0 volumetric How rate, m^/s volumetric flow rate per width in transverse direction, m^/s volumetric How rate per width in <^< direction, m^/s dimensionless How rate radius of journal, m radius of shaft, m radius of journal, m 269 Copyright © 2004 Marcel Dekker, Inc. dimensionless resultant load in a journal bearing resultant load per unit width in a journal bearing, N/m load per width perpendicular to line of centers, N/m load per width along line of centers, N/m normal applied toad, N angle used in defining film thickness in journal bearing Sommerfeld variable eccentricity ratio, e/e absolute viscosity, Pa-s absolute viscosity at p = 0 and constant temperature, Pa-s attitude angle angle in cylindrical coordinates angle where o!p/d<^=0 angle where p = 0 and dp/^ = 0 angular velocity, 2 . . rad/s ^%, angular velocity of surface &, rad/s 270 FUNDAMENTALS OF FLUID FILM LUBRICATION Figure : Hydrodynamic journal bearing geometry Introduction The past two chapters have dealt with slider bearing pads as used in thrust bearings. The surfaces of thrust bearings are perpendicular to the axis of rotation as shown in Fig. . This chapter and the next deal with journal bearings, where the bearing surfaces are parallel to the axis of rotation. Journal bearings are used to support shafts and to carry radial loads with minimum power loss and minimum wear. The journal bearing can be represented by a plain cylindrical sleeve (bushing) wrapped around the journal (shaft) , but the bearings can adopt a variety of forms. The lubricant is supplied at some convenient .
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