Font size
WorksheetsDay 51-nov 12-worksheet-PWD-pipe flow,dimensional analysis,BLT
Total questions: 15
Worksheet time: 10mins
For maximum power transmission through a pipe, the friction head loss satisfies:
hf = H
hf = H/2
hf = H/3
hf = 2H/3
The vertical distance between the Total Energy Line (TEL) and the Hydraulic Gradient Line (HGL) at any section is equal to:
pressure head
velocity head
datum head
friction head loss
For laminar flow in a circular pipe, the ratio of maximum to average velocity equals:
1
1.5
2
0.5
In dimensional analysis, the Froude number is primarily relevant to:
closed‑conduit viscous flow
free‑surface gravity‑dominated flow
compressible high‑speed flow
capillary‑dominated flow
Over a flat plate, the local laminar boundary‑layer thickness varies approximately as:
δ/x ~ Rex0
xδ∼Rex−1/2
xδ Rex−1/5
xδ∼Rex−1
In a pipe that discharges to the atmosphere, the HGL at the outlet passes through the pipe centerline.
True
False
For a streamlined body, the pressure drag is dominant and skin‑friction drag is negligible.
True
False
Assertion (A): For laminar flow in a circular pipe, the velocity profile is parabolic. Reason (R): In laminar flow, shear stress varies linearly with radius.
(a)
The head loss due to a sudden enlargement is given by which expression?
(a)
For pipes in series, discharge is the same in each pipe. The total head loss across the line is best represented by:
H = Σ4f(L/D)(V2/(2g))
H = Σf(D/L)(V2/g)
H=ΣkV2
H = Σ V
Maximum efficiency of power transmission through a pipe equals:
50%
60%
66.67%
75%
According to Buckingham–Pi, the number of dimensionless groups for a problem is:
n + j
n − j
j − n
n × j
Water flows in a 120 m long, 200 mm diameter pipe at a mean velocity V = 1.8 m/s. Take Darcy f = 0.02. Compute the friction head loss using the Darcy–Weisbach relation.
(a)
A flow expands from 100 mm to 200 mm diameter with the same volumetric flow rate Q = 0.010m3/s . Compute the head loss due to sudden enlargement h_se.
(a)
A reservoir head H = 24 m feeds a long pipeline. The system is adjusted for maximum power transmission.Friction head is
(a)
