Apparatus required :

CCL₄ manometer, H_g manometer.

Procedure :

1. Keep the valve leading to fittings open and valves leading to other lines closed.
2. Keep the bypass valve completely open and the main valve completely closed. Switch on the pump.
3. Connect a CCLmanometer to the pressure taps across the globe valve. Ensure that no air bubbles present and height in both the limbs of manometer are the same.
4. Set a flow rate of water through the pipe by opening the main valve and throttling the bypass valve suitably using the rotameter.
5. Note down the rotameter reading and manometer reading after a steady state is attained.
6. Increase the flow rate of water by opening the main valve and throttling the bypass valve suitably and repeat step 4 and 5.
7. Use mercury manometer for higher flow rates.
8. Take eight readings with CCL₄ manometer as well as with H_g manometer.

Data :

Diameter of the pipe connected to globe valve = D =      m
Density of water = =     kg/m

Viscosity of water = =cp=     kg/ms

Density of CCl4 = 1600 kg/m
Density of Hg = 13600 kg/m

Calculations :

1. Flow rate:
2. ∆Hm is cm of manometric fluid:
3. Volumetric flow rate, Q =m³/s
4. Pressure drop in m of water hf =
5. Cross sectional area of the pipe A =
6. Average velocity through the pipe = V=Q/A =   m/s
7. Reynolds number
8. Friction factor f is calculated using f =
9. Equivalent length of Globe valve:

Result :

Report equivalent length of the fitting and compare with other types.