GATE CE: Fluid Mechanics Champion Quiz 3 for ESE & GATE CE Exams

Question 1

A 2 km long pipe of 0.2 m diameter connects two reservoirs. The difference between water levels in the reservoirs is 8m. The Darcy–Weisbach friction factor of the pipe if 0.04. Accounting for frictional, entry and exit losses, the velocity in the pipe (in m/s) is:

Question 2

An incompressible homogenous fluid is flowing steadily in a variable diameter pipe having the large and small diameters at 15 cm and 5 cm, respectively. If the velocity at a section at the 15 cm diameter portion of the pipe is 2.5 m/s, the velocity of the fluid (in m/s) at a section falling in 5 cm portion of the pipe is ___________

Question 3

Why are surge tanks used in pipe line?

Question 4

Consider fully developed flow in a circular pipe with negligible entrance length effects. Assuming the mass flow rate, density and friction factor to be constant, if the length of the pipe is doubled and the diameter is halved, the head loss due to friction will increase by a factor of __________.

Question 5

Three pipes A, B and C have the following basic geometries :

If these pipes are connected in series, by assuming the value of friction factor f to be same for all the three pipes and the equivalent pipe, this set of pipes ill series is equivalent to a pipe of length L and diameter D and friction factor f with the equivalent length L being equal to

Question 6

In a pipe network:

Question 7

Water flows through a 10 mm diameter and 250 m long smooth pipe at an average velocity of 0.1 m/s. The density and the viscosity of water are 997 kg/m³ and 855 x 10^-6Ns/m² respectively. Assuming fully-developed flow, the pressure drop (in Pa) in the pipe is _______.

Question 8

The circular water pipes shown in the sketch are following full. The velocity of flow (in m/s) in the branch pipe “R” is

Question 9

A vertical clean glass tube of uniform bore is used as a piezometer to measure the pressure of liquid at a point. The liquid has a specific weight of 15 kN/m³ and a surface tension of 0.06 N/m in contact with air. If for the liquid, the angle of contact with glass is zero and the capillary rise in the tube is not to exceed 2 mm, what is the required minimum diameter of the tube?

Question 10

Which combination of the following statements about steady incompressible forced vortex flow is correct?
P: Shear stress is zero at all points in the flow.
Q: Vorticity is zero at all points in the flow.
R: Velocity is directly proportional to the radius from the centre of the vortex.
S: Total mechanical energy per unit mass is constant in the entire flow field.