14.6. Hydraulic Radius Concept

Try these first

1. 1.

   What is the formula for calculating hydraulic radius?

   Hint

   Think about what each component represents.

2. 2.

   Define wetted perimeter.

   Hint

   Consider how water interacts with the channel.

3. 3.

   What does the hydraulic radius measure?

   • Flow velocity
   • Cross-sectional area
   • Ratio of area to wetted perimeter

   Hint

   Recall the formula for hydraulic radius.

4. 4.

   True or False: The hydraulic radius decreases as the wetted perimeter increases.

   • True
   • False

   Hint

   Think about the relationship in the formula for R.

5. 5.

   For a circular pipe with a diameter of 1 m, what is the hydraulic radius? Then compare this with a rectangular channel having a width of 2 m and depth of 1 m.

   Hint

   Remember: diameter in circular channels relates differently to area and perimeter.

6. 6.

   Design a trapezoidal channel with a base width of 3 m, a depth of 2 m, and side slopes of 1:2. Calculate the hydraulic radius and explain its implications in flow dynamics.

   Hint

   Break down the channel design into the base area and the lateral areas for easier computation.