Shear Stress

The force per unit area acting parallel to a surface, caused by fluid Viscosity and velocity gradients. It is the resistance to flow in viscous fluids.

Mathematical Expression

${\tau }_s=\mu \frac{d\gamma }{dt}$

Where:

• ${\tau }_s$ = shear stress
• μ = dynamic Viscosity
• $\frac{d\gamma }{dt}$ = shear strain rate

Notes

• Higher viscosity → higher shear stress
• Steeper velocity gradient → higher shear stress