C

B3C032S Pages: 3

6. a. A submerged weir 2m long has height of water on the upstream 0.15m and downstream

0.075m above the top of the weir. Find the discharge over the weir, if the coefficients of
discharge for free and drowned portions are 0.58 and 0.8 respectively. (8) b. Oil of specific
gravity 0.75 flows through a 15cm diameter pipe under a pressure of 98.1kN/m7. If the datum
is 3m below the centre of the pipe and the total energy per unit weight with respect to datum

is 20m, calculate the discharge (7)

PART C
Answer any two full questions.
Derive the Hagen - Poiseuille equation for laminar flow through a pipe. (20)
Two reservoirs with a difference in water levels of 180m are connected by a 64km long pipe
of 600mm diameter and darcy’s friction factor f= 0.015. Determine the discharge through
the 010൦. Inorder to increase this discharge by 50% another additional pipe of the same
diameter is laid from the first pipe and connected to the reservoir. Determine the

length of the additional pipe. (20)

Ree |.

Additional pipe
180m

SS

a. A rectangular flat plate of length a and width b is towed length-wise through water with

velocity Ua and subsequently width-wise with velocity Up. The boundary layer is laminar

and the plate experiences equal drag in both cases. Determine the ratio of velocities Ua and

‎in terms of dimensions of the plate. (10)‏ متا

‎0. Water is delivered by a 15cm diameter pipe at 60 litres per second. Calculate the pressure
difference between two points 300m apart on the same horizontal line.

‎(Take friction factor = 0.022) (10)

‎नमन

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