Flow Flashcards
What are the four requirements of accurate flow measurements
Safety
Efficient industrial processes
Environmental Standards
Financial Control
What are flow meters
Instruments used to measure flow in units of volume per unit time
What are the 2 categories of flow meters and their classes
Quantity- +ve displacement
Rate of flow - velocity type, differential mass type
Eg of quantity meters
Nbr
Nutting disc
Bellows type
Rotating vane type
Eg of rate of flow meters
MTVV
Magnetic Flowmeter
Turbine “
Vortex “
Variable “
What is the difference between quantity and rate of flow meters
Quantity measure volume whilst rate of flow measures the volume and time
if the flow is not steady, however, the total quantity will be represented by
f by the area
under the curve obtained by plotting the rate
of flow against time
principle of operation of differential flow meters
The principle of operation is based on the fact
that when a restriction is placed in a fluid
stream, the fluid must move faster in order to
pass the same quantity through the pipe as
passed before the restriction was added.
What are metering pumps
positive displacement
pumps, which provide a predictable and
accurate rate of fluid flow
Concentric orifice
Central hole/orifice for clean fluids
ie liquid no gas bubbles
Gas no liquids
Segmental
Another of suspended material not abrasive
what are meters
mir
devices used to
measure, record, and indicate the value of a
measured variable.
Archimedes principle
Any object that is partially or completely submerged in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces.”
Categories of flow measurement
Continuous level measurement
Point level measurement
Eg of continuous
GUUMM
Gauge glass
Use of floats
Ultrasonic
measure of electrical capacitance
measure of head pressure
