1.9. Turbulent Flow in Pipes

Try these first

1. 1.

   What is eddy viscosity?

   Hint

   It varies based on flow conditions.

2. 2.

   Define Reynolds shear stress.

   Hint

   It involves fluctuating velocity components.

3. 3.

   What is the primary cause of increased shear stress in turbulent flow?

   • Viscous resistance
   • Eddy viscosity
   • Pressure differences

   Hint

   Think about the chaotic nature of turbulent fluid movements.

4. 4.

   True or False: In turbulent flow, viscous shear stress plays a significant role throughout the entire fluid.

   • True
   • False

   Hint

   Reflect on where turbulence primarily occurs.

5. 5.

   Calculate the turbulent shear stress using Prandtl’s theory if the average velocity gradient (du/dy) is 0.5 s⁻¹ and the mixing length (lm) is 0.2 m.

   Hint

   Ensure all units align for a proper calculation.

6. 6.

   Discuss how the value of the von Karman constant impacts the estimation of turbulent shear stress in a practical engineering application.

   Hint

   Consider the effects of turbulence on structural stresses in engineering.