1.8. Differential Form of the Equation

Try these first

1. 1.

   What is the definition of laminar flow?

   Hint

   Think about how a straight stream flows.

2. 2.

   What is the Reynolds number threshold for laminar flow?

   Hint

   Remember the general numbers given.

3. 3.

   What flow regime is associated with a Reynolds number less than 2300?

   • Turbulent
   • Laminar
   • Transitional

   Hint

   Recall the threshold values discussed.

4. 4.

   True or False: Turbulent flow is characterized by regular and streamlined motion.

   • True
   • False

   Hint

   Think about how turbulent flow looks in real life.

5. 5.

   A fluid with a viscosity of 0.001 Pa·s flows through a 5 cm diameter pipe at a velocity of 1 m/s. Calculate the Reynolds number and determine if the flow is laminar or turbulent.

   Hint

   Don't forget to convert units if needed.

6. 6.

   For flow through a circular pipe, derive the equation of velocity as a function of radius under laminar flow conditions. Consider the assumptions discussed.

   Hint

   Start from the defined shear stress τ = -μ(du/dr), integrate considering boundary conditions.