muhammadahmed191141@gmail.com

2. OBJECTIVE
The objective of our presentation is comparisons of
different flow measuring devices.

3. FLOW METERS
A flowmeter (or flow meter / flow indicator / flow
gauge depending on industry) is simply defined as a
device used to measure the speed at which a gas or
liquid is moving through a pipe.

4. TYPES OF FLOW MEASUREMENT
Mass flow rate Volume flow rate

5. FLOWS

6. BERNOULLI EQUATION

7. TYPE OF FLOW METER
Differential Pressure
Flow Meters
• Orifice meter
• Venturi meter
• Rota meter
• Pitot tube
Displacement
Flow
• Positive Displacement
Flow
• Gear Flow Meters
• Turbine flow meter
• Paddlewheel Flowmeters
• Variable-Area Flowmeters
(Rotameters)
Electromagnetic Flow
Meter
• Ultrasonic Flowmeters
• Doppler-Effect Ultrasonic Flowmeters
• Vortex Flowmeters
• Laser Doppler velocimetry (LDV)
• Particle image velocimetry (PIV)

8. DIFFERENTIAL PRESSURE
FLOW METERS

9. ORIFICE PLATES
• An orifice plates is a plate with a circular hole in the middle of it.
• Flow through hole, velocity will increase and the pressure will
decrease.

10. ORIFICE PLATES
• Sharp square edged cylindrical throat.
• Pressure difference proportional to flow rate.
• Cheap, good performance and reliability.
• Moderate cost with Simple metrology.

11. VENTURI METER
• A meter consist of short converging pipe relatively longer pipe diverging with suitable pressure
differential measurement.
• When fluid passes through converging side its velocity increases maximum at throat and and become
same after passing throat.

12. VENTURI METER
• Best accuracy.
• Least head loss as compared to orifice &
nozzle meter.
• Can be used with dirty fluids also.
• Relatively expensive.

13. VARIABLE-AREA FLOWMETERS (ROTA METER)
• A rotameter is device measure flow rate of liquid and gas in a closed tube.
• pressure drop remain constant and flow varies directly with cross sectional area

14. ROTA METER
Working Principle
• When fluid enter from bottom it exert force on float
• float move up
• gravitational and force exerted by liquid become equal equilibrium exist
• float becomes stationary
• flow rate measure by graduation scale on float

15. PITOT TUBE
Pitot tube measure local velocity at given point in stream not average velocity in pipe.

16. PITOT TUBE

17. DISPLACEMENT FLOW

18. POSITIVE DISPLACEMENT FLOWMETERS
o It has a low pressure drop
o used with high- or low viscosity liquids at temperatures up to 230°C
o pressures up to 7 Mpa
o flow rates of up to 700 gal/min (or 50 L/s).

19. PADDLEWHEEL FLOWMETER

20. ELECTROMAGNETIC FLOW
METER

21. ULTRASONIC FLOWMETERS

22. DOPPLER-EFFECT ULTRASONIC FLOWMETERS

23. VORTEX FLOWMETERS

24. With best wishes of success
for my presentation
Thank you!