Relation between Theory, Experiment, and Practice in Journal Bearing Design

Abstract

The first section of the paper is devoted to the correlation of experimental and theoretical research on journal bearings embracing the angles of 360 deg., 180 deg., and 120 deg., and attempts to combine hitherto isolated experimental data by making use of the results of Kingsbury's experiments based upon an electrical analogy. The possible causes of divergence in the results obtained by different workers are enumerated and their effect on the general agreement explained. There is considerable experimental evidence to support the basic principles of the method of design derived in the preceding paper by Dr. Swift.The second section analyses current methods of design in the light of these principles, and explains the reasons for departure from the theoretical method in some cases. Particulars relating to journal bearings used in various types of machines are tabulated, and values of the dimensionless criteria used in actual practice are compared with those suggested by theory. Design examples are worked out, and results tabulated, in order to explain the methods which may be employed in order to secure optimum running conditions in various circumstances, and their resultant effect on performance.A summary is given in the last section of the existing state of knowledge relating to journal bearings, considered from the point of view of the designer. Further data still necessary are enumerated and the avenues of research yet to be explored in order to obtain this knowledge are explained.