ASME MFC-21.1:2015 pdf free download

ASME MFC-21.1:2015 pdf free download.Measurement of Gas Flow by Means of Capillary Tube Thermal Mass Flowmeters and Mass Flow Controllers.
flow calibration: the act of comparing the fluid mass flow rate measured by a flowmeter under test with that of a flow calibration standard in the same conduit. Also, the act of adjusting the output of the flowmeter under test to bring it to a desired value, within a specified tolerance, for a particular value measured by the standard. See Mandatory Appendix I and calibration (para. 2.1).
gas corwersion factor: a constant factor, often called a K-factor, that relates the flow calibration data found with a reference gas to another gas. The gas conversion factor is the ratio of the product of standard mass density times the coefficient of specific heat (p.. c) of the reference gas to that same product for another gas (see section 7). See Mandatory Appendix l,flow calibration, and reference gas.
general purpose MFM or MFC: a capillary tube thermal MFM or MFC used for general purpose industrial and laboratory applications (see para. 3.2).
Iwat capacity: the thermodynamic property of a gas that measures its ability to store thermal energy (enthalpy). See sensor tube.
heat capacity rate: the product (q.wc,,) of the gas mass flow rate in the sensor tube times the coefficient of specific heat at constant pressure that is a primary component of the heat capacity of the gas. The output of capillary tube thermal mass flowmeters and mass flow controllers is proportional to the heat capacity rate in the linear range of the instruments, See beat capacity and sensor tube.
instrument(s): specifically for this text, the term instrurnent(s) is defined as a capillary tube thermal mass flow- meter, mass flow controller, or both collectively.
intrinsic sensor noise: noise intrinsic to the sensor tube itself, as distinguished from noise associated with the electronics. See electronics and se;rsor tube.
K-factor: see gas conversioti factor.
laminar flow element: the bypass in a capillary tube thermal mass flowmeter or mass flow controller that has a fully developed laminar velocity distribution in its flow passages. The ratio of the mass flow rate through the laminar flow bypass to that of the sensor tube is a constant. See Inipass. biipass ratio,fully developed velocity distribution (para. 2.1), laminarfiow (para. 2.1), and scissor tube.
laminar hydrodynamic entry length: the length at the entrance of the sensor tube required for the velocity distribution of its internal flow to have attained, within a certain pen.’entage (usually 2%), a fully developed laminar velocity distribution. See fully developed velocity distribution (para. 2.1) and laminar flow (para. 2.1).
leak raW: the rate of leakage of
(a) the process gas in the instrument to the outside environment.