14.3.3. Force Components

Try these first

1. 1.

   What are the main forces acting on water in an open channel?

   Hint

   Think about the motion and resistance.

2. 2.

   What does the hydraulic radius represent?

   Hint

   Consider how we describe the shape of a channel.

3. 3.

   What are the main forces acting on water in open channel flow?

   • Gravity and pressure
   • Gravity and friction
   • Friction and tension

   Hint

   One of these forces is always a pull in one direction.

4. 4.

   True or False: In supercritical flow, the water depth is greater than in subcritical flow.

   • True
   • False

   Hint

   Think about the definitions of both flows and their characteristics.

5. 5.

   A trapezoidal channel has a bottom width of 4 m, side slopes of 2:1, and a depth of 3 m. Calculate the hydraulic radius.

   Hint

   Use the trapezoid area formula and remember to find both the area and perimeter carefully.

6. 6.

   Compare the energy loss in a long rectangular channel with laminar flow versus turbulent flow. Discuss factors impacting these losses.

   Hint

   Consider the nature of flow and how it interacts with the channel surface.