flow measurement Flashcards
An _____ is a primary flow element consisting of a thin circular metal plate with a sharp-edged round hole in it
Oriface plate
An _____ is the tubing or piping connection that connects flowmeter taps to any differential pressure instrument
Impulse line
what two forces are always present in a closed pipe?
Static head due to pressure
Static head due to elevation
When steam flow is measured, the measuring instrument must be located _____ the flow element
Below
Venturi tubes, orfice plates, and flow nozzles measure what?
Flow
_____ is the ratio of maximum flow to minimum flow at the desired measurement
Rangeability
When liquid flow is measured, the presence of _____ in impulse lines ruins accuracy
Air bubbles
A _____ valve is a valve used at a differential measuring instrument to equalize pressure in a differential instrument
Blocking
Pressure sensing taps are located _____ and _____ from a flow nozzle
Upstream
Downstream
When can flow measurement become inaccurate?
When flowing conditions change from when the system was designed
A _____ tube is a primary flow element consisting of an aerodynamic internal cross section with the low pressure connection at the throat
Low Loss
A _____ is a pressure connection
Tap
A _____ is a primary flow element consisting of a fabricated pipe section with a converging inlet section, a straight throat, and a diverging outlet section
Venturi tube
A _____ is a small metal or plastic rotameter with an adjustable valve at the inlet or outlet of the meter to control the flow rate of the purge fluid
Purge Meter
A _____ meter is a mechanical flowmeter consisting of turbine blades mounted on a wheel that measure the velocity of a liquid steam by counting the pulses produced by the blades as they pass an electromagnet pickup
Turbine
A _____ or _____ meter is a flowmeter consisting of an orifice as part of the float assembly that acts as a guide
Shaped-float or Orfice
A _____ shredding meter is a flowmeter consisting of a pipe section with a symmetrical vertical bluff body (partial dam) across the flowing stream
Vortex
What is a thermal mass meter?
Two thermal sensors with a heat element between them that measure the temperature difference on either side
how does an ultrasonic flowmeter measure flow?
Sound emitters send sound waves with and against the current to measure the difference in travel time for the waves
with a vortex shredding meter, the frequency of the fluid that is released can be measured with _____ meters
Ultrasonic
A _____ meter is a flowmeter consisting of a stainless steel tube lined with a non-conductive material, with two electrical coils mounted on the tube like a saddle
Magnetic
The detectors for coriolis meters consist of a _____ and _____ mounted on each tubing section at the points of maximum motion
Magnet
Coil
A coriolis meter can also measure _____
Density
A _____ meter is a mass flowmeter consisting of specially formed tubing that is oscillated at a right angle to the flowing mass of fluid
Coriolis
