Pitot Tube Apparatus test

              Pitot Tube Experiment

◼️Aim: 

       Calculate the velocity of flow by pitot tube.

◼️ Material on Construction:

       A pitot tube is Mounted on 25 mm GI pipe line which is connected to a pump. The pump is mounted on one end and the collecting tank is mounted on the other end of the MS fiver coated sump tank. The setup is provided with control valves and also a by - pass valve to regulate the flow. A glass tube and a wooden scale are mounted on one of the side of the collecting tank to view the water level inside.

◼️ Theory:

       A pitot tube is advice used for measuring the velocity of flow at any point in a pipe or in a channel. It is based on the principle. That if the velocity of flow at a point becomes zero. The pressure there is increased due to the conversion of kinetic energy into pressure energy. In its simplest from, the pitot-tube consists of a copper tube bent at right angles as shown in the fig.

◼️ Specification:

◾Diameter of the pipe (d) = 25 mm

◾ Rise in collecting tank water level R = 
0.1 m

◾Area of collection tank (1×b) = 0.3×0.3 = 0.09 m
◾Time taken for collecting of water = t(sec)

◾Density of manometer liquid ( mercury) Sm = 13.600 kg/m³

◾ Density of water, Sw = 1000 kg/m³

◼️ Operating procedures:

1. Fill up the water to the sump up to certain level.

2. Now open the by - pass valve.

3. Plug the main chord to the 230 volts AC mains.

4. Switch on the pump.

5. Now close the by - pass valve slightly and simultaneously open the pitot - tube control valve and set the flow for some flow rate.

6. Now close the collecting tank drain valve so that the water starts collecting.

7. Note down the time taken for 10 cm rise in the water level.

8. Calculate the amount of water collecting in the tank per time taken in second.

9. Repeat the above steps for different flow rates.

10. Now open the by pass valve before switch off the pump.

◼️ Formula:

1. Actual discharge:

QAct = Actual volume of water collected/Time taken.           ........ m²/sec

Q = A×h/1000×T.    ....... m³/sec
A = Area of collection tank m²

h = height of water collect in mm.

T = time taken in sec. For collecting tank in sec.

2. Velocity at any point:

V = Cv√(2gh).    ..... m/sec

H = 12.6×h  ( h = manometer reading in mm of Hg)

Cv = velocity of coefficient or pitot-tube coefficient = 0.98

V = velocity of flow

hw = manometer reading or pressure head.

g = gravitational constant.

3. Theoretical discharge:

QThe = velocity of any point × area of pipe ..... m³/sec

Area of the pipe = π×d²/4 m²

Diameter of pipe = 25mm = 0.025m

Area of pipe = 4.908 × 10^-4 m²