Fluid Mech. – II (CE-604 (A)) - Important Questions

Explain separation of boundary layer, including effect of pressure gradient and methods to prevent it.

Derive an expression for velocity distribution in terms of average velocity for rough pipes.

Write short notes on laminar and turbulent boundary layers and laminar sublayer.

Define and explain the hydraulic gradient line and total energy line (energy gradient line) for fluid flow in pipes.

Derive Chezy's and Manning's formulae for open channel flow.

Explain the most economical circular channel section for the condition of maximum velocity.

Determine the maximum flow rate in a concrete-lined circular channel of 3.6 m diameter with bed slope 1:700 and C = 50.

Sluice gate discharges water into horizontal rectangular channel with velocity 10 m/s and depth 1 m: determine sequent depth after hydraulic jump and loss of energy in total head.

Derive an expression for depth of hydraulic jump in terms of the upstream Froude number.

Write about Magnus effect.

Explain the drag forces acting on a sphere.

Using Prandtl's universal velocity distribution for turbulent flow in a rough pipe of 300 mm diameter, determine the velocity at the centre and the shear velocity if the average velocity is 2.5 m/s. Take friction factor f = 0.02.

A Pelton wheel has a mean bucket speed of 15 m/s with a jet of water flowing at the rate of 0.8 m3/s under a head of 150 m. The buckets deflect the jet through an angle of 165 degrees. Calculate the power delivered to the runner and hydraulic efficiency. Take coefficient of velocity Cv = 0.98.

State which turbine requires a draft tube and derive the expression for draft tube efficiency.

Prove that the manometric head of a centrifugal pump can be expressed as Hmano = AN^2 + BNQ + CQ^2 where A, B, C are constants.