Fluid Mechanics & Machineries Very Important Questions

Fluid Mechanics & Machineries Very Important Questions

Unit – 1

Explain the terms :

(i) dynamic viscosity (ii) Kinematic Viscosity. Give their dimensions

A 15cm diameter vertical cylinder rotates concentrically inside

What is the difference between U-tube differential manometers

Where are they used-

What are the gauge pressure and absolute pressure

Unit – 2

Obtain an expression for continuity equation for a three-dimensional

The velocity potential function is given by F = 5(x2 – y2 )

calculate the velocity components at the point (4,5)

Explain about velocity potential.

A stream function is given by – = 5x-6y.

Calculate the velocity components and also magnitude

Unit – 3

From the principle of Euler’s equation of motion derive Bernoulli’s

Water if flowing upto a pipe of 5 cm diameter

Find the total head or total energy per unit weight of the water

What is a minor energy loss (head losses)-

Derive an expression for determining loss of head due to sudden

At a sudden enlargement of a water main from 240 mm to 480 mm

diameter the hydraulic gradient rises by 10mm. Estimate the rate of flow.

Unit – 4

Explain about Laminar boundary layer.

What are the methods of preventing the separation of boundary layer-

Explain about turbulent boundary layer

Oil with a free stream velocity of 2 m/s flows over a thin plate 2 m

Calculate the boundary layer thickness and the shear stress a

determine the total surface resistance of the plate.

What is the relation between pressure and density of a compressive

i. Isothermal process and ii. Adiabatic process.a

A gas with a velocity of 300 m/sec is flowing through a horizontal pipe

Define Mach number.

What is the significance of Mach number in compressible fluid flows-

Find the sonic velocity for the following fluids :

i. Crude oil of specific gravity 0.8 bulk modulus 153036 N/cm2.

ii. Mercury having a bulk modulus of 2648700N/cm2.