Question

When a thin cylindrical shell is subjected to an internal pressure there will be?

Answer 1

7. 

When a thin cylindrical shell is subjected to an internal pressure, there will be

[A].

a decrease in diameter and length of the shell

[B].

an increase in diameter and decrease in length of the shell

[C].

a decrease in diameter and increase in length of the shell

[D].

an increase in diameter and length of the shell

Answer: Option D

Ravali said: (Feb 21, 2013)  

How both diameter and length increases. I think so it is not correct.

In my view diameter decreases, length increases. Could anyone support me.

Abdul Rajik said: (Sep 23, 2013)  

YES, In my thought of view is increase the Dia and Decrease the length.

Akshay said: (Jan 15, 2014)  

Why both are not decrease?

Swaroopkumar said: (Apr 9, 2014)  

It is based on pressure inside the shell.

Hardik said: (Apr 28, 2014)  

Pressure depend on volume of cylinder, so both is uniformly increasing. All related data is constant. So this is correct.

D' Nainesh said: (May 12, 2014)  

Its simple logic. When we blow air into balloon, its whole (3D) dimension will increase. Because the pressure inside it is uniformly distributed over its entire internal area.

Same concept is here. Here the internal pressure is not uniaxial in which longitudinal dimension will increase and lateral will decrease. It is of 3 dimensional. So given answer is correct.

Aman Bansal said: (Aug 8, 2014)  

Due to internal pressure, both d & L will increase as volume will also increase.

Vitthal said: (Jan 21, 2016)  

Pressure acting uniformly over entire inside area which tends it not to contract.

D Rahul said: (Apr 25, 2016)  

I think in thin cylindrical shells the (radial stress is) & (longitudinal stress). So, the diameter must increase and length should decrease.

It is an option (b).

Sridevi said: (Nov 3, 2016)  

Answer is correct both length and diameter increases as pressure is acting uniform in all direction. It is not an axial force to increase the length and decrease diameter.

Answer 2

Answer:

It may be noted that when the shell is subjected to an internal pressure, there will be an increase in diameter as well as the length of the shell.

Explanation:

When a thin cylindrical shell is subjected to an internal pressure, its wall be subjected to lateral strain, the effect of which there will be change in dimensions (i.e. length and diameter) of the shell.

Thin cylinder pressure walls are subjected to two types of stresses which is:

Circumferential stress (force tending to rupture vessel circumferentially)

Longitudinal stress (force tending to rupture vessel longitudinally)

Both the stresses are tensile in nature.