Stresses in Rotating Disc — Lesson 5

This lesson covers the concept of stress distribution in a rotating disc. It explains how each material element in the disc is subjected to body forces when rotating, and how these forces act in the radial direction. The lesson further discusses the radial displacement of a point in the disc, the expressions for strains, and the conditions for plane stress in the disc. It also elaborates on the equilibrium equations and how they are satisfied in the disc. The lesson concludes with an explanation of how to calculate the torque capacity of a shaft and hub assembly in a rotating disc.

Video Highlights

00:53 - Explanation of the forces acting on the material elements of the rotating disc.
06:52 - Discussion on the stresses in a rotating disc.
15:07 - Explanation of the boundary conditions for the radial stress.
20:10 - Discussion on the variation of stresses in a solid and hollow cylinder.
28:43 - Explanation of the stress amplification in a rotating disc with a small hole.
34:18 - Explanation of the concept of shrink fitting in assembling a gear on a shaft.
48:00 - Discussion on the calculation of the torque capacity in shrink fitting.

Key Takeaways

- The material elements in a rotating disc are subjected to body forces acting in the radial direction.
- The radial displacement of a point in the disc is a function of the radius alone, with no tangential displacement.
- The radial and shear strains in the disc are determined by specific expressions.
- The equilibrium equations are satisfied in the disc, with the shear stress being absent.
- The torque capacity of a shaft and hub assembly in a rotating disc can be calculated using specific formulas.