19.3.2. Choosing Control Volume

Try these first

1. 1.

   What is a control volume in fluid mechanics?

   Hint

   Think about the area we analyze.

2. 2.

   How many components are there in a stress tensor?

   Hint

   Relate it to normal and shear stresses.

3. 3.

   What are stress tensors primarily used for?

   • To measure temperature
   • To analyze fluid forces
   • To calculate volume

   Hint

   Think about how forces are represented.

4. 4.

   True or False: Body forces only act at the surface of a fluid.

   • True
   • False

   Hint

   Consider the force's distribution.

5. 5.

   Calculate the total pressure force and gravity force acting on a subset control volume from a fluid at rest.

   Hint

   Use both surface and volume integrals.

6. 6.

   Given a fluid flow situation, define an appropriate control volume and justify your design choice.

   Hint

   Reference how pressure distributions might cancel.