What is the wetted perimeter of a 2 m diameter sewer running at a partial flow depth of 50 cm____________________ ?
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Answer: D. 2 /3
Explanation
Partial flow calculations determine the wetted perimeter using central angle geometry. For a two-meter diameter sewer running at fifty centimeters, the arc length evaluates to two pi D over three. Trigonometric principles relate flow depth and diameter to the wetted boundary length. Sewer pipes operate under partial flow conditions during dry weather daily cycles. Wetted perimeter calculations are essential for applying open channel flow equations. Geometric proportions dictate flow velocity and hydraulic efficiency in circular conduits.
Hydraulic engineers evaluate partial flow capacities to design efficient sewer networks. Understanding wetted perimeter aids in predicting sediment transport and friction losses. Accurate calculations prevent operational issues in municipal wastewater collection systems. Alternative fractions like one-third or zero over two lack correct geometric derivation. Incorrect formulas fail to incorporate the proper central angle for the given flow depth. Standard hydraulic calculations confirm two pi D over three as the accurate wetted perimeter.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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