Quartz capillary flow meter for gases
- 1 March 2004
- journal article
- Published by AIP Publishing in Review of Scientific Instruments
- Vol. 75 (3) , 772-779
- https://doi.org/10.1063/1.1642751
Abstract
This article describes an accurate meter for gas flow rates below 1000 μmol/s. (1 μmol/s≅1.3 cm3/min at 0 °C and 1 atm). Two gauges measure the input and output pressures as the gas flows through a flow element consisting of either a single quartz capillary or an array of parallel quartz capillaries. A hydrodynamic model determines the molar flow rate from the two pressures, the gas temperature, and the gas properties. Measurements with nitrogen demonstrated that three flow elements could span the flow range from 0.1 to 1000 μmol/s with a standard uncertainty of less than 0.03%. Additional measurements with helium, argon, propane, and sulfur hexafluoride demonstrated that, by using the capillary radius determined for nitrogen, the model could predict the flow rates of gases with widely varying properties.Keywords
This publication has 8 references indexed in Scilit:
- NIST–IMGC comparison of gas flows below one litre per minuteMetrologia, 2003
- A survey of flow at low pressuresPublished by Elsevier ,2002
- Laminar flow of four gases through a helical rectangular ductAIChE Journal, 2001
- Thermodynamic Properties of Sulfur HexafluorideInternational Journal of Thermophysics, 2000
- Data on Internal Rarefied Gas FlowsJournal of Physical and Chemical Reference Data, 1998
- Thermal effects in compressible viscous flow in a capillaryInternational Journal of Thermophysics, 1993
- Compressible laminar flow in a capillaryJournal of Fluid Mechanics, 1993
- Theoretical Analysis of Pressure Drop in the Laminar Flow of Fluid in a Coiled PipeTransactions of the Society of Rheology, 1970