Test: Fluid Flow Kinematics - 2 | 10 Questions MCQ Test

QUESTION: 1

A 2-D flow having velocity V = (x + 2y + 2)i + (4 - y)j will be

A.
compressible and irrotational
B.
compressible and not irrotational
C.
in compressible and irrotational
D.
in compressible and not irrotational

Solution:

QUESTION: 2

In a flow net

A.
the velocity in the stream tube is directly proportional to the mesh size
B.
the velocity at a boundary surface is always zero
C.
the pressure difference between any two meshes can be determined ' by the application of the Bernoulli equation
D.
the velocity potential increases in the down stream direction

Solution:

QUESTION: 3

A stream function is

A.
defined only for incompressible flow.
B.
defined for irrotational flow
C.
defined when the flow is continuous
D.
defined only for steady flow

Solution:

A stream function is defined by following characteristic:
The partial derivative of stream function w.r.t y will give velocity in x-direction.
The partial derivative of stream function w.r.t x will give velocity in negative y-direction.
It is valid for steady, incompressible flow since, is satisfies the continuity equation

QUESTION: 4

The continuity equation for steady incompressible flow is expressed in vector notation as

A.
∇.q = 0
B.
∇².q = 0
C.
∇ x q = 0
D.
∇² x q = 0

Solution:

QUESTION: 5

In a converging steady flow there is

A.
no acceleration
B.
no temporal acceleration
C.
only convective acceleration
D.
convective and temporal acceleration

Solution:

QUESTION: 6

In two dimensional flow, the equation of a streamline is given as

Solution:

QUESTION: 7

The concept of stream function which is based on the principle of continuity is applicable to

A.
three dimensional flow
B.
two dimensional flow
C.
uniform flow cases only
D.
irrotational flow only

Solution:

Velocity potential function is valid for 3-dimensional flow while stream function is valid for 2 dimensional flow.

QUESTION: 8

Which of the following velocity potentials satisfies continuity equation?

A.
x²y
B.
x² - y²
C.
cosx
D.
x² + y²

Solution:

For the velocity potential function to satisfy continuity equation:
Where φ is velocity potential, φ = x² - y² satisfies this equation

QUESTION: 9

In a two dimensional incompressible steady flow around an airfoil, the stream lines are 2 cm apart at a great distance from the airfoil, where the velocity is 30 m/sec. The velocity near the airfoil, where the stream lines are 1.5 cm apart, is