Accession Number : ADA303479

Title :   Deformation Behavior of Thin Lubricant Films at Elevated Pressure-Viscometric Functions.

Descriptive Note : Annual rept.,

Corporate Author : GEORGIA INST OF TECH ATLANTA SCHOOL OF MECHANICAL ENGINEERING

Personal Author(s) : Bair, Scott

PDF Url : ADA303479

Report Date : JAN 1996

Pagination or Media Count : 32

Abstract : Although normal stress differences in liquids have conventionally been associated with polymers, aspects of rheological behavior in lubricated concentrated contacts suggest that normal stress difference may be significant in even low molecular weight liquids sheared under high pressure and high shear stress. A torsional flow rheogoniometer was constructed for use at high (300 MPa) pressure. Four typical liquid lubricants were investigated, including one polymer/mineral oil solution. Shear stress and N1- N2 are reported as functions of shear rate. The effect of pressure variation is reported for two liquids. Results are compared with predictive techniques and a molecular dynamics simulation. Simple low molecular weight lubricant base oils can generate measurable and significant normal stress differences when sheared at high shear stress. (AN)

Descriptors :   *STRESS ANALYSIS, *LUBRICANTS, STRESS STRAIN RELATIONS, PRESSURE GRADIENTS, MATHEMATICAL MODELS, POLYMERS, DEFORMATION, VISCOELASTICITY, MOLECULAR WEIGHT, THIN FILMS, HIGH PRESSURE, PRESSURE MEASUREMENT, SHEAR STRESSES, THERMAL CONDUCTIVITY, NONEQUILIBRIUM FLOW, MINERAL OILS, VISCOSITY, TORSION, LUBRICATING FILMS, COUETTE FLOW, RHEOMETERS, VISCOMETERS.

Subject Categories : Mechanics
      Lubricants and Hydraulic Fluids

Distribution Statement : APPROVED FOR PUBLIC RELEASE