The Gas Liquid Interface and the Load Capacity of Helical Grooved Journal Bearings

Self-acting helical-grooved journal bearings, lubricated by an incompressible Newtonian liquid and operating under laminar conditions, have under favorable conditions a negligible leakage due to the inward pumping action of the grooves. During concentric running, the axial position of the gas liquid interface created in the grooved section of the bearing does not vary in circumferential direction (local effects due to a finite number of grooves are not taken into account). During eccentric running, however, the width of the liquid region, i.e., the interface varies in circumferential direction due to pressure differences in the lubricant film. For a complete herringbone journal bearing the interaction between the shape of the interface and the pressure distribution has been studied both theoretically and experimentally.