4. Velocity Profiles

Try these first

1. 1.

   Define laminar flow.

   Hint

   Think about how a stream of oil flows smoothly.

2. 2.

   What is the significance of Reynolds number?

   Hint

   It's a dimensionless quantity related to the nature of flow.

3. 3.

   What is the boundary layer thickness typically defined as?

   • When velocity reaches 100% of free stream
   • When velocity reaches 99% of free stream
   • Both A and B

   Hint

   Think about the concept of the boundary layer ceasing to exist.

4. 4.

   True or False: The laminar sub-layer does not exist in turbulent flows.

   • True
   • False

   Hint

   Recall the characteristics of the turbulent boundary layer.

5. 5.

   Describe a scenario in an engineering application where understanding boundary layer behavior is critical. How would you use this knowledge in design?

   Hint

   Consider where drag and lift are crucial in flight.

6. 6.

   Explain how varying Reynolds numbers affect fluid flow in a pipe and how this relates to boundary layers.

   Hint

   Focus on how flow behavior changes in relation to speed and viscosity.