BOOK REVIEWS book. Chap. 6 on "Lateral Buckling of Beams" has been thoroughly revised. Chap. 7 on "Buckling of Rings, Curved Bars, and Arches" differs only slightly from Chap. 4 of the first edition. Chaps. 8 and 10, treating the bending of thin plates and shells, are essentially the same as the old Chaps. 6 and 8. In Chap. 9 on "Buckling of Thin Plates" more cases are discussed than in the first edition, and Chap. 11 on "Buckling of Shells" has been similarly expanded. Throughout the book, references to recent literature have been added.

This work is concerned with an evaluation of the performance of a gas journal bearing using a spring supported compliant foil as the bearing surface. The analysis, conducted for both single and multipad configurations, is concerned with the effects that the various structural, geometric, and operational variables have on bearing behavior. Following the solution of the relevant differential equation, tabular or graphical solutions are provided for a range of relevant geometric and operational parameters. The solutions include values of the colinear and cross-coupled spring coefficients due to both structural and hydrodynamic stiffness. Desirable design features with regard to start of bearing arc, selection of load angle, number of pads and degree of compliance are discussed.

This work is concerned with an evaluation of the performance of a gas thrust bearing using what amounts to a spring supported compliant foil as the bearing surface. To enhance the load capacity of such a device, the leading portion of the foil is given an appropriate converging geometry. The paper offers an analytical investigation of the elastohydrodynamics of the compliant foil bearing, and the effects that the various structural and operational variables have on bearing behavior. Following the solution of the relevant differential equation, the geometry of the thrust sector is first optimized, then solutions are provided for a range of relevant geometrical and operational parameters. The parametric study shows that the optimum geometry for a bearing with the common OD to ID ratio of 2 is β=45deg,b=0.5,h¯1>10 In addition to the geometric parameters, there are also the structural parameters of the foil. The load capacity is shown to increase as the compliance of the bearing rises. While at moderate Λ’s high values of compliance yield the highest load capacity, at high Λ, the optimum compliance is some intermediate value, in our case, α* = 1. Since the stiffness of the bearing is a function of both the structural and hydrodynamic film stiffnesses, high loads tend to flatten the values of K for the softer bearings, leaving essentially the structural stiffness as the dominating spring constant.

An analysis is conducted and solutions are provided for the effect of centrifugal forces on the hydrodynamics of high-speed thrust bearings and seals. First, a scrutiny of the individual inertia terms of the Navier-Stokes equations delineates the circumstances under which the centrifugal term (u2/r) becomes the dominant component. A Reynolds equation incorporating centrifugal forces is then derived for finite sectorial configurations operating under incompressible laminar conditions. Thermal effects are included. The equation is solved by finite difference methods. The results show that at the upper limits of laminar operation centrifugal forces reduce considerably the load capacity and alter the pattern of lubricant flow. As a result, at sufficiently high velocities the inflow of lubricant at the inner radius of a sectorial configuration may bring about the scavenging of lubricant from wide portions of the bearing surface, producing a form of thrust bearing cavitation. Design features which would reduce the negative consequences of centrifugal action are outlined, including the introduction of radial tapers.

An analytical solution of 3-lobe journal bearings is offered based on the solution of the finite Reynolds equation. Expressions for eccentricity, lubricant flow, power loss, and spring constant are given for a range of L/D ratios and ellipticities. The bearing is shown to be of superior quality both in its stability characteristics and in its hydrodynamic performance. Charts and equations for setting design requirements and calculating performance are given in simple convenient form.