Test: Hydraulics & Fluid Mechanics - 1 - Civil Engineering (CE) MCQ

1000 litre=1 m³=1,000,000 cm³, 

So 1 litre=1,000,000/1,000=1000cm³.

Alternatively, the Mach Number can be expressed with the density and the bulk modulus for elasticity as,

M = v (ρ/ E)^1/2

The bulk modulus elasticity has the dimension pressure and is commonly used to characterize the fluid compressibility.

This air is carried away by the flowing water, which results in creating a negative pressure beneath the nappe. The negative pressure drags the lower side of the nappe towards the surface of the weir wall. This results in more discharge than the normal discharge. In order the keep the atmospheric pressure in the space below the nappe holes are made through the channel walls which are connected through the pipes to the atmosphere as shown in figure. Such holes are called 'Ventilation' of a weir.

For one dimensional flow, the velocity is the function of single coordinate (i.e) u= f(x).

Let u be the velocity.

The function u = f(x) is the straight line.

Therefore one dimensional flow is the straight line flow.

It is due to the capillary action in which the water rises in the tube due more adhesive force betwwen the tube surface and water tham the water-water cohesive force

Actual Formula for Discharge for broad crested weir is Q = C_d (g)^0.5 b^2/3 H^3/2

For MaximumDischarge = (9.81)^1/2 (2/3)^3/2 = 1.7048~1.71(approx).

Discharge stands for Q=A*V.
As water enters through inlet, it has larger area in comparison to "throat" of venturimeter. Water entered is assumed to have zero losses in pipe and venturimeter so, discharge at inlet should be equal to discharge outlet. As discharge is same throughout pipe and venturimeter and area of throat is lesser than inlet & outlet both, its velocity will be higher at throat than at inlet & outlet both( Q= const. so Velocity is inversely proportional to Area).

Coefficient of friction= Friction Factor/4

Darcy Weisbach friction factor for laminar flow = 64/Rn

Coefficient of friction= 16/Rn

HGL = Pressure head + Datum head --->{1}.
TEL = Pressure head + Velocity head + Datum head --->{2}.

From equation 1 and 2 it is clear that. TEL will be lead to HGL by velocity head.

The hydraulic power can be transmitted by a pipeline. For a maximum power transmission, the head due to friction in the flow equals to one third of the head at source to be transmitted. The maximum power transmitted efficiency is 67%.