2.1. Problem 7: Shear Stress Determination

Try these first

1. 1.

   What is shear stress?

   Hint

   Think about forces acting on flat surfaces.

2. 2.

   Convert 10 cm to meters.

   Hint

   Remember 1 cm = 0.01 meters.

3. 3.

   What is shear stress at the wall denoted as?

   • tau_max
   • tau_wall
   • tau_not

   Hint

   It’s a constant in turbulent flow equations.

4. 4.

   True or False: Laminar flow has a constant cross-sectional area.

   • True
   • False

   Hint

   Consider the profile shape when answering.

5. 5.

   A pipe with an average height of irregularities is 0.15 mm. If the wall shear stress is 4.9 N/m² and viscosity is 0.01 Stokes, describe the boundary type.

   Hint

   Calculate Re* using u*k/ν.

6. 6.

   Given shear stress values and velocity profiles, create an analysis discussing how you would calculate τ₀ for a non-circular pipe flow system.

   Hint

   Remember to adjust for geometric factors in your calculations.