Hydraulics - Engineering

Q1:

The shear stress distribution in viscous fluid through a circular pipe is :

A maximum at the centre

B maximum at the inside of surface

C same throughout the section

D none of these.

ANS:C - same throughout the section

"same throughout the section" refers to an idealized scenario that doesn't apply to the shear stress distribution in viscous fluid through a circular pipe under typical conditions. In reality, the shear stress distribution in viscous fluid through a circular pipe is not uniform or "same throughout the section." Instead, it follows a non-uniform distribution, with the highest shear stress occurring at the inside surface or wall of the pipe, where the fluid velocity is zero due to the no-slip condition. This non-uniform distribution is characteristic of laminar flow in a pipe, where the velocity profile is parabolic. The shear stress varies from zero at the center of the pipe (where the velocity is maximum) to a maximum value at the wall. Therefore, the shear stress distribution in viscous fluid through a circular pipe is not the same throughout the section. Instead, it exhibits a non-uniform distribution with the highest shear stress occurring at the inside surface or wall of the pipe.