FLOW MEASUREMENT

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FLOW MEASUREMENT

• CHAPTER 2

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OBJECTIVES

• After you study this chapter, you should be able
  to
• Define flow measurement.
• Describe the importance of flow measurement.
• Explain the basic operation, list the advantages
  and disadvantages of each flow measurement device.

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TOPIC COVERED

• Introduction to Flow Measurement
• Flow Measuring Device
• 1. Differential Pressure Meter
• - Orifice, Venturi. Nozzle
• 2. Electromagnetic Flowmeter
• 3. Vortex Flowmeter
• 4. Turbine Flowmeter
• 5. Ultrasonic Flowmeter

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INTRODUCTION

• What is flowrate??
• Amount of material passing one point for certain
  time
• Give one simple method to measure
• 1. Water flowrate from tap water.
• 2. Gas flowrate filling in a bottle

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INTRODUCTION

• Why flow is prime important parameter?
• Most process involves moving material from one
  part of the plant to another
• Flow of
• Material - Gas, liquid, solid particle
• Energy Power
• Thermal energy

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TASK 1

• Discuss in group, write the basic operation of
  each instrument given. Each group members must be
  able to explain the basic operation of the
  instrument. List the advantages and disadvantages
  of the instrument.

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Flow Nozzle

• Consist of an elliptical converging section and
  cylindrical throat section.
• Suitable for high-velocity, non-viscous, erosive
  flows.
• Flow Nozzles have a smooth elliptical inlet
  leading to a throat section with a sharp outlet.
  This restriction in the fluid flow causes a
  pressure drop.
• This device has a greater overall pressure loss
  or operating cost in terms of head pressure than
  a Venturi but offers lower installation costs.

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Venturi
Orifice
Nozzle
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Electromagnetic Flowmeter
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Vortex Flowmeter

• Bluff Body obstruction to flow
• Pressure difference main stream and bluff body
  vortices

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Turbine Flowmeter

• Pulse frequency is proportional to the velocity

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Ultrasonic Flowmeter

• Ultrasonic flowmeters clamped on / inline
• Doppler Model
• - frequency shift
• - Particles in the fluid

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• Time Transit Model
• - Difference in frequency proportional to
  average fluid velocity flowrate

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Minute Paper
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To be continued