1. I am trying to analyse the hydrostatic pressures exerted on a submarine at depth Firstly If I model the submarine as being two hemispherical ends with a cylindrical section. Am I correct to model them seperately then combine the results at the end to calculate the deformation or is there a better method of doing this. Variables p=pressure R=radius t=wall thickness E=youngs modulus Pr=poissons ratio 2. I have used the equations (please ignore the way the equations are laid out it is my personal notation in MATLAB) sphere_stress=-(p*R)/(2*t); hoop_stress= -(p*R)/t longitudinal_stress =-(p*R)/(2*t) then to calcualte the strains on the cylindrical part. Circumferential_strain=(1/E)*(hoop_stress-Pr*longitudinal_stress) Longitudinal_strain= (1/E)*(longitudinal_stress-Pr*hoop_stress) I am struggling with the equation for the strain acting upon the spherical ends. Once I have the strain acting upon the sphere I can then calculate the change in length diameter and volume Basically I am after a hint to how to calculate the strain on the spherical ends and to have my method of modelling the submarine confirmed as being accurate or being informed if there is a better way. I apologise if this is in the wrong section.