Method of Similitude and Introduction to Fractional Analysis of Overall Equations

Abstract

In the nineteenth century a number of workers, most notably Lord Rayleigh, commonly solved problems of fractional analysis by direct use of the idea of similarity combined with the formation of force ratios. During the twentieth century this method seems to have lost favor and has been replaced almost entirely by the use of the pi theorem except in the work of a few authors in fluid mechanics (see, for example, Vennard,⁵² Chap. 7). In fact, the method seems to be so little used today that no accepted name for it exists; for purposes of reference, it is called the method of similitude throughout the present volume.