Shells:

This unit presents the analysis of thin shells subjected to internal and external pressure. This is an extension of the previous unit describing thin cylindrical shells. In this unit, stresses and strains induced in shells will be found out based on the geometry of the shell.

We shall begin by defining a thin spherical shell identifying the assumptions to be made for the analysis. After discoverning the stresses in the material of the shell, strains shall be calculated.

We will then analyse doubly curved shells describing their difference from a spherical shell.

Conical shells shall be analysed considering their geometry for arriving at the stresses.

Objectives

After studying this unit, you should be able to

• explain a shell and put down the assumptions made in the analysis,
• find out stresses in a spherical shell,
• determine the strains produced in a spherical shell,
• compute the stresses in a doubly curved shell,
• get expressions for the analysis of conical shell, and
• workout problems involving shells.