Midterm Preparation Flashcards
Causes of flow
Fluid velocity depends on
differential head pressure
Causes of flow
Increase pressure or force
increases fluid flow rate
Causes of flow
ΔP Forces fluid to
flow through pipe
Causes of flow
ΔP created by
physical (height difference) or mechanical means, pumps/compressors
factors that affect selection of flow measuring method
- Pressure
- Temperature
- Velocity
- Density
- Viscosity
Force per unit area
Pressure
Pressure Effect
Liquids generally _______, little change in _____ when pressure exerted
- incompressible fluids
- volume
Pressure Effect
Gases are ________
compressible
Temperature
Boiling Water at STD =
212o F, 100oC
Temperature
F ̊ + 459.69 =
Rankine (R)
Temperature
C ̊ + 273.15 =
Kelvin (K)
Temperature
Freezing =
32 ̊ F , 0 C ̊ (absolute temp 491.69R & 273.15 K)
Most flow problems require the use of absolute temperature
Temperature Effect
In general fluids will decrease in density as the temperature ____
increases
Temperature Effect
As the density _____ with the rise of temperature the volume of the fluid will increase
decreases
Temperature Effect
Increase in the volume due to temperature will need to be _____ for accurate Flow measurement
compensated
Mass of substance per unit volume
Density
Weight due to g per unit volume
Specific Weight
SI term for Specific Gravity is
RELATIVE DENSITY
Density Effect
Use density of a fluid to calculate the ____
mass flow
Resistance of flow of a fluid
Stickiness of a fluid
Common unit is centipoise (cP) 1/100 of a poise
Dynamic Viscosity
ratio of thedynamic viscosity (μ)
to the Density (ρ) of the fluid
Common units are centistokes (cS)
Kinematic Viscosity
laminar flow
Turbulent flow
Properties of Pipe & Flow
Rough inside of pipe will ___ flow of fluid along pipe wall
slow
Properties of Pipe & Flow
Most meters need profile to be flat as in____
turbulent flow
Properties of Pipe & Flow
Smooth pipe preferred ________
upstream of meter
Purpose of Pump & Compressor
If the fluid is incompressible such as a liquid needs a _____ to move it
pump
Purpose of Pump & Compressor
If the fluid is compressible such as a gas need a ______ to move it
compressor
Orifice plate with flange taps for gas or liquid flow
Orifice plate c/w orifice plate changer, to change orifice while on line
Venturi tube for gas or liquid flow
Flow nozzle normally used for steam flow
Pitot tube, normally used for flue gases in stacks or
water flow in large pipes
Weir, for flow in large aqueducts, i.e. irrigation canals
Flow straightening vane, used before or after orifice to remove turbulence
Turbine or propeller type meter for gas or liquid
Variable area flow indicator or rotameter
Mass flow with integer transmitter
Vortex meter sensor for liquid or gas
Magnetic flowmeter with integral transmitter for conductive liquids
Magnetic Flowmeter
Thermal mass flowmeter
Coriollis flowmeter
Sonic / Ultrasound flowmeter
Positive displacement meter c/w totalizer and indicator
Ultrasonic (sound frequency) flowmeter,
Doppler or Transit Time
Averaging pitot tube for very large flue stacks
Primary Elements - Flow
Generic orifice plate
Restriction plate
Primary Elements - Flow
Orifice plate in quick-change fitting
Primary Elements - Flow
Concentric circle orifice plate
Restriction orifice
Primary Elements - Flow
Eccentric circle orifice plate
Primary Elements - Flow
Circle quadrant orifice plate