Pitot Tube(velocity profile)

PITOT TUBE’S EXPERIMENT

GROUP IV (BATCH –I)

Manne Venkata Harish Babu ME08B013

Manoj Kumar Tripathi ME08B014

Medarametla Krishnakalyan ME08B015

Mohammad Salimuddin ME08B016

AIM :

To determine the velocity profile of

air flowing through a pipe using

Pitot’s tube

BACKGROUND:

The Pitot’s tube is widely employed

to measure fluid velocities in

flowing fluids

One of the major reasons for this

is that it can be used with

“minimal disturbance” to the flow

Continued…

In measurement system terminology,

the sensor is the Pitot tube itself.

The measurand (velocity) is converted

to a differential pressure, which is then

converted by an intermediate modifying

device (manometer) to a differential

height of manometer fluid that is read

from a calibrated scale

Construction of Pitot tube:

THEORY:

Pitot Tube is aligned with the flow direction

Assuming an inviscid, incompressible flow

V – velocity of air

a – density of airPstag – total pressurePstat – static pressure

Continued..

Now, this , the dynamic pressure

is converted into differential height of

the fluid( water, in our case) of

manometer, hence

2a

1ρ v ρ

2wgh

2a

1ρ v

2

Experimental Set-up:

A 2 inch diameter GI pipe was

connected to a 1 inch diameter GI pipe

via an expansion joint, to increase the

resolution and accuracy of the

readings.

Continued…

Pitot tube was attached to a U-tube

filled with water(manometer)

The experiment was done at a pressure

of 10 kgf/cm2

Complete set-up:

Reading Evidence (Video):

Observation :S.No. Distance from the centre

x, (cm)

Height difference

h , (cm)

Velocity , V (m/s)

1. -2.5 0.65 10.3

2. -2.0 1.95 17.84

3. -1.5 2.9 21.76

4. -1.0 3.6 24.24

5. -0.5 4.2 26.19

6. 0 4.5 27.11

7. 0.5 4.15 26.03

8. 1.0 3.55 24.07

9. 1.5 2.9 21.76

10. 2.0 1.9 17.61

11. 2.5 0.7 10.69

Velocity Profile:

0

5

10

15

20

25

30

-3 -2 -1 0 1 2 3

Velocity, V(m/s)

Velocity, V(m/s)

Result :

The velocity profile of air flowing

through the given tube, is almost

parabolic.

Sources of error:

Misalignment of the tube axis and the

velocity vector , exposing the static taps

to some component of the velocity

Influence of the hole-tip spacing

Wall effect

THANK YOU