17.4.1. Control Volume Application

Try these first

1. 1.

   Define incompressible flow and state the condition for it.

   Hint

   Consider the definition of Mach number.

2. 2.

   What is a control volume in fluid mechanics?

   Hint

   Think about regions in space through which fluid flows.

3. 3.

   What condition must the Mach number meet for flow to be considered incompressible?

   • Greater than 0.3
   • Less than 0.3
   • Equal to 1

   Hint

   Recall the definition of the Mach number.

4. 4.

   True or False: In a control volume, mass can sometimes vanish completely during analysis.

   • True
   • False

   Hint

   Think about the principles of conservation.

5. 5.

   A tank with two inflows is filled with water at varying speeds. If inflow velocities are 0.5 m/s and 0.8 m/s with diameters of 25 mm and 35 mm respectively, calculate the change in water height over a 5-minute interval if the tank area is 2 m².

   Hint

   Use the inflow formula to find volumes, then convert to height over time.

6. 6.

   You have a channel where the upstream velocity is 0.6 m/s and downstream is 0.4 m/s, with a channel width of 1.5 m. Determine the seepage rate given the channel's average depth is 0.2 m.

   Hint

   Calculate flow before and after across given areas.