ASME MFC-1:2014 pdf free download Glossary of Terms Used in the Measurement of Fluid Flow in Pipes
1GENERAL1.1 Scope
This Standard consists of a collection of definitionsof those terms that pertain to the measurement of fluidflow in pipes.The definitions provided also give guid-ance for recommended usage in the application of flowmeasurement devices.
1.2 Organization
This Standard is organized alphabeticlly. Symbols nor-mally applied to various quantities are tabulated insection 3.
1.3 References
This Standard was compiled from many sources,including various reports and standards from TheAmerican Society of Mechanical Engineers (ASME), theAmerican Gas Association (AGA), the AmericanPetroleum Institute (API),the International Society ofAutomation (ISA), the British Standards Institute (BSI),the International Organization for Standardization(ISO), the National Institute for Standards andTechnology (NIST), and the International Organizationof Legal Metrology (OIML).
2GLoSSARY OF TERMS
absolute pressure: algebraic sum of the atmospheric pres-sure and gauge pressure.
absolute static pressure of a fluid: static pressure of a fluidmeasured with reference to a perfect vacuum.
acceptance test: the evaluating action(s) to determine if aninstrument satisfactorily meets its performance criteria,permitting the owner / purchaser to formally accept itfrom the supplier.
accuracy of measurement: the extent to which a given mea-surement agrees with a reference for that measurement;often used by manufacturers to express the performancecharacteristics of a device.
NOTE:“Accuracy” is not the same as “uncertainty” (see “uncer-tainty of measurement””).
acoustic natching layer: material comprising one or morelayers, selected to maximize the acoustic coupling coeffi-cient between two media.
acoustic path: the path that the acoustic signals follow asthey propagate through the measurement sectionbetween the transducer elements.
acoustic ratio: the differential pressure ratio divided bythe isentropic exponent (compressible fluid).
air: mixture of gases and associated water vapor sur-rounding the earth; dry air plus its associated watervapor. The term is used synonymously with atmosphere.air, dry: mixture of dry gases present in the atmosphere.ambient temperature: temperature of the atmosphere mea-sured in the immediate vicinity of the point of measure-ment and unaffected by wind or other atmosphericphenomena.
annular chanber: piezometer ring integral with the pipeor the primary device that simplifies the constructionof annular pressure taps.
annular space: area between the tapered tube and thefloat that normally increases as the float rises.
area mmeters: flowmeter in which a variation in the crosssection of the fluid stream under constant head is usedas an indication of the rate of flow, e.g., a float is sus-pended in a vertical tapered tube and as the fluid flowrate changes, the position of the float in the tube changes.arithmetic mean: the sum of values divided by the numberof values, also called “average.”
NOTES:
(1)The term “mean” is used generally when referring to a popula-
tion parameter, and the term, “average,” when referring to theresult of a calculation on the data obtained in a sample.(2)The average of a simple random sample taken from a popula-
tion is an unbiased estimator of the mean of this population.Other estimators,such as the geometric or harmonic mean,the median, or the mode are sometimes used.
atmospheric pressure: force per unit area exerted by theatmosphere.
NOTE:Standard atmospheric pressure is 760 mm of mercury at0°C. This is equivalent to 101.325 kPa and 14.696 psia.
aoverage oalue: arithmetic mean of n readings of thequantity x. The average value x is calculated using thefollowing formula
ASME MFC-1:2014 pdf free download
