Thursday, 5 March 2015

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)
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
What are the methods of preventing the separation of 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.