CU06997 Lecture 8 ; Exercises
|Link to lecture 8
Link to les 8
Link to computation
|At the end of the lecture, there is already a first introduction|
– equivalent roughness k-concrete = 1,5 mm, k-PVC = 1 mm
– width weir = 2 m
Calculate for each pipe: A, R (submerged) , C (rough boundary) and bed slope
|Question 1 (Only wastewater, no precipitation)
a)In this situation the PVC250 pipe is half filled with waste water. Calculate the discharge and velocitiy.
b)Check if the flow is turbulent
|Question 2 (Only wastewater, no precipitation)The supply of waste water on P3 and P2 is 10 l/s (both manholes). The pump capacity is 20 l/s. Calculate the water depth in pipe P2-P3 . Also calculate the velocity and hydraulic radius.|
|Question 3 (Rain, precipitation)
3,75 ha paved area is connected to P2, 1,1 ha paved area is connected to P3. The rainfall intensity is 60 l/s.ha.
The figures show that the amount of rainwater in the sewer is much more than the amount of waste water. For the next questions we will neglect Waste water and the pump capacity.
b)Indicate the direction of the flow with rainfall. Calculate the discharge for each pipe.
c)Calculate the specific height (H) at the weir (c=1,8)
d)Calculate the head loss for branches P4-P3, P3-P2 and P2-P1. Also calculate the velocity head and velocity for each branch. Use Chezy’s formula.
e)Calculate for each manhole the energy level and water level
f)Check if the flow is turbulent