Two reservoirs at different levels are connected by two parallel pipes of diameter '2d' and 'd'. The ratio of the flows in the two pipes (larger: smaller) is
⇒ Q1/Q2 = 4/1
A 15 cm diameter pipe carries a flow of 70 L/s of an oil (RD = 0.75). At a section 12 cm above the datum the pressure is vacuum of 2 cm of mercury, if the kinetic energy correction factor a for this section is 1.1, the total head at the section in metres of oil is
Total head = + ρ/y + z (here p is negative).
The loss of head due to friction in a pipe of uniform diameter in which viscous flow is taking place is
where Re = flow Reynold’s number
In the Moody diagram the third parameter is ks/D. Here ks is
A compound pipe of diameters d1, d2 and d3 having length l1, l2 and l3 respectively, is to be replaced by an equivalent pipe of uniform diameter d and length l. The size of the equivalent pipe is given by
For pipes in series equivalent pipe is given by:
For pipes in parallel equivalent pipe is given by
In a pipe flow, the shear velocity u. is related to the Darcy-Weisbach friction factor f as u./V =
Two pipe systems are said to be equivalent when
An oil of kinematic viscosity 0.25 stokes flows, through a pipe of diameter 10 cm. The flow is critical., at a velocity of
Re = 2000 = VD/v
2000 = ⇒ V = 0.5 m/sec
Which one of the following phenomena in a pipe flow is termed as water hammer?
The pressure at the summit of a syphon is
The centre line of pipe is well above the hydraulic grade line and therefore the pressure is negative or below atmospheric.