rdfs:comment
| - L'acronyme SCFM est une unité de mesure de débit de gaz fréquemment utilisé dans les pays anglo-saxons qui signifie Standard Cubic Feet per Minute, soit en français pied cube par minute d'un gaz ramené aux conditions normales de température et de pression. (fr)
- Standard cubic feet per minute (SCFM) is the molar flow rate of a gas expressed as a volumetric flow at a "standardized" temperature and pressure thus representing a fixed number of moles of gas regardless of composition and actual flow conditions. It is related to the mass flow rate of the gas by a multiplicative constant which depends only on the molecular weight of the gas. There are different standard conditions for temperature and pressure, so care is taken when choosing a particular standard value. Worldwide, the "standard" condition for pressure is variously defined as an absolute pressure of 101,325 pascals (Atmospheric pressure), 1.0 bar (i.e., 100,000 pascals), 14.73 psia, or 14.696 psia and the "standard" temperature is variously defined as 68 °F, 60 °F, 0 °C, 15 °C, 20 °C, or 2 (en)
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has abstract
| - L'acronyme SCFM est une unité de mesure de débit de gaz fréquemment utilisé dans les pays anglo-saxons qui signifie Standard Cubic Feet per Minute, soit en français pied cube par minute d'un gaz ramené aux conditions normales de température et de pression. (fr)
- Standard cubic feet per minute (SCFM) is the molar flow rate of a gas expressed as a volumetric flow at a "standardized" temperature and pressure thus representing a fixed number of moles of gas regardless of composition and actual flow conditions. It is related to the mass flow rate of the gas by a multiplicative constant which depends only on the molecular weight of the gas. There are different standard conditions for temperature and pressure, so care is taken when choosing a particular standard value. Worldwide, the "standard" condition for pressure is variously defined as an absolute pressure of 101,325 pascals (Atmospheric pressure), 1.0 bar (i.e., 100,000 pascals), 14.73 psia, or 14.696 psia and the "standard" temperature is variously defined as 68 °F, 60 °F, 0 °C, 15 °C, 20 °C, or 25 °C. The relative humidity (e.g., 36% or 0%) is also included in some definitions of standard conditions. In Europe, the standard temperature is most commonly defined as 0 °C, but not always. In the United States, the standard temperature is most commonly defined as 60 °F or 70 °F, but again, not always. A variation in standard temperature can result in a significant volumetric variation for the same mass flow rate. For example, a mass flow rate of 1,000 kg/h of air at 1 atmosphere of absolute pressure is 455 SCFM when defined at 32 °F (0 °C) but 481 SCFM when defined at 60 °F (16 °C). In countries using the SI metric system of units, the term "normal cubic metre" (Nm3) is very often used to denote gas volumes at some normalized or standard condition. Again, as noted above, there is no universally accepted set of normalized or standard conditions. (en)
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