ISO 14511:2019

INTERNATIONAL ISO
STANDARD 14511
Second edition
2019-01
Measurement of fluid flow in closed
conduits — Thermal mass flowmeters
Mesure de débit des fluides dans les conduites fermées — Débitmètres
massiques par effet thermique
Reference number
ISO 14511:2019(E)
©
ISO 2019

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ISO 14511:2019(E)

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ii © ISO 2019 – All rights reserved

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ISO 14511:2019(E)

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 General terms . 1
3.2 Specific terms . 2
4 Selection of thermal mass flowmeters . 4
5 Capillary thermal mass flowmeter (CTMF meter) . 5
5.1 Principles of measurement . 5
5.2 Typical design . 8
5.3 Applications and limitations of use . 8
5.3.1 Gas property effects . 8
5.3.2 Application and fluid properties . 9
5.3.3 Temperature effects . 9
5.3.4 Pressure effects . 9
5.3.5 Pulsation effects . 9
5.3.6 Pressure loss . 9
5.3.7 Cleanness of the gas . 9
5.3.8 Mounting orientation effects .
...