Question

Please explain the meaning of equal stress (or strength) design and the approximate design geometry in the rotating disk section

Answer 1

1. If at each point the equivalent stress corresponding to a particular theory of strength is equal to the ultimate strength of the material, It will be called equal strength structure. An equal stress structure at all points of the body, the stress state is the same. While in the case of inhomogeneous bodies, ultimate strength may be variable equal strength and equal stress structures oth are of different concepts.

2. In case of to obtain approximate design geometry for the rotating disk section, the rotating disks uniform cross-section is very uneconomical. some of the research has given a comprehensive analysis of the problem and suggested as a hyperbolic curve for the profile of the cross-section of the disk. while some developed an approximate method which replaces the actual disk by a series of rings with uniform thickness. Mathematical programming approach to optimum design of rotating disks which optimized the cross-section of the rotating disk using constraints on frequency and stresses. Sometimes the disks with an inner diameter of the hub smaller than the diameter of the shaft are taken, heated and then fitted on to the shaft. After cooling the shaft and the disks are fitted tightly and it gives rise to pressure between them. However, in these investigations, the methods of stress analysis are not very accurate particularly in the region of stress concentration. The disk is approximated by a number of rings, the optimum thicknesses of which are determined by mathematical programming.further, you can go through this reference paper for obtained approximate design geometry. https://drive.google.com/file/d/1mp2hM9UlUbBJpZ075UR3CXC8yTmv-4nb/view?usp=sharing