GROUP IV (BATCH – I) 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) (manometer) to a differential height of manometer fluid that is read from a calibrated scale
Cons Co nstru truct ctio ion n of Pi Pito tott tu tube be:
THEORY:
Pitot Tube is aligned with the flow direction Assuming an inviscid, incompressible flow
V a
Pstag Pstat
– velocity of air – density of air – total pressure – static pressure
Continued.. 1
2
Now, this 2 , the dynamic pressure is converted into differential height of the fluid( water, in our case) of manometer, hence ρav
1 2
ρav
2
ρwgh
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) water(manometer)
The experiment was done at a pressure of 10 kgf/cm2
Complete
set-up:
Reading Evidence (Video):
Observation : S.No.
Distance from th the ce centre Height difference x, (cm) 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
1 0.
2.0
1.9
17.61
1 1.
2.5
0.7
10.69
Velocity Profile: Velocit elo city y,V(m/s) V(m /s) 30
25
20
15 Velocity, V(m/s)
10
5
0 -3
-2
-1
0
1
2
3
Result : The velocity profile of air flowing f lowing through the given tube, is almost parabolic.
Sources of error:
Misalignment 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
