Time-Correction Model Based on Diverter Speed for a pVTt Gas Flow Primary Standard

The volumetric primary standard with a constant volume (pVTt) determines the flow rate from the rate of change of gas density in the defined measuring volume. The key element of the measuring system that uses the flying start–stop method is a diverter. This paper presents a time correction model tha...

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Main Authors: Primož Žibret, Gregor Bobovnik, Jože Kutin
Format: Article
Language:English
Published: MDPI AG 2022-05-01
Series:Sensors
Subjects:
Online Access:https://www.mdpi.com/1424-8220/22/11/4001
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author Primož Žibret
Gregor Bobovnik
Jože Kutin
author_facet Primož Žibret
Gregor Bobovnik
Jože Kutin
author_sort Primož Žibret
collection DOAJ
description The volumetric primary standard with a constant volume (pVTt) determines the flow rate from the rate of change of gas density in the defined measuring volume. The key element of the measuring system that uses the flying start–stop method is a diverter. This paper presents a time correction model that adapts the correction according to the diverting speed implemented in our pVTt system developed for flow rates smaller than <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>12</mn><mspace width="3.33333pt"></mspace><mi mathvariant="normal">m</mi><mi mathvariant="normal">g</mi><msup><mi>min</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></semantics></math></inline-formula>. A detailed study of the diverter’s effects on the effective collection time and two methods for determining the time correction are presented. One is based on the ISO 4185 standard and the other on measurements of the dynamic pressure upstream of the diverter. A set of correction time measurements were made at different diversion speeds to define the correction model at a flow rate of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>9</mn><mspace width="3.33333pt"></mspace><mi mathvariant="normal">m</mi><mi mathvariant="normal">g</mi><msup><mi>min</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></semantics></math></inline-formula>. The results show very good agreement between the measurements with both methods and the defined correction model. Additional measurements were made at smaller flow rates and the results indicate the independence of the time correction from the measured flow rate.
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spelling doaj.art-5c06e88fd49d4756ba82676a34dd01782023-11-23T14:47:06ZengMDPI AGSensors1424-82202022-05-012211400110.3390/s22114001Time-Correction Model Based on Diverter Speed for a pVTt Gas Flow Primary StandardPrimož Žibret0Gregor Bobovnik1Jože Kutin2Laboratory of Measurements in Process Engineering, Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva 6, SI-1000 Ljubljana, SloveniaLaboratory of Measurements in Process Engineering, Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva 6, SI-1000 Ljubljana, SloveniaLaboratory of Measurements in Process Engineering, Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva 6, SI-1000 Ljubljana, SloveniaThe volumetric primary standard with a constant volume (pVTt) determines the flow rate from the rate of change of gas density in the defined measuring volume. The key element of the measuring system that uses the flying start–stop method is a diverter. This paper presents a time correction model that adapts the correction according to the diverting speed implemented in our pVTt system developed for flow rates smaller than <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>12</mn><mspace width="3.33333pt"></mspace><mi mathvariant="normal">m</mi><mi mathvariant="normal">g</mi><msup><mi>min</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></semantics></math></inline-formula>. A detailed study of the diverter’s effects on the effective collection time and two methods for determining the time correction are presented. One is based on the ISO 4185 standard and the other on measurements of the dynamic pressure upstream of the diverter. A set of correction time measurements were made at different diversion speeds to define the correction model at a flow rate of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>9</mn><mspace width="3.33333pt"></mspace><mi mathvariant="normal">m</mi><mi mathvariant="normal">g</mi><msup><mi>min</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></semantics></math></inline-formula>. The results show very good agreement between the measurements with both methods and the defined correction model. Additional measurements were made at smaller flow rates and the results indicate the independence of the time correction from the measured flow rate.https://www.mdpi.com/1424-8220/22/11/4001flow rate measurementpVTttime correctiondiverter
spellingShingle Primož Žibret
Gregor Bobovnik
Jože Kutin
Time-Correction Model Based on Diverter Speed for a pVTt Gas Flow Primary Standard
Sensors
flow rate measurement
pVTt
time correction
diverter
title Time-Correction Model Based on Diverter Speed for a pVTt Gas Flow Primary Standard
title_full Time-Correction Model Based on Diverter Speed for a pVTt Gas Flow Primary Standard
title_fullStr Time-Correction Model Based on Diverter Speed for a pVTt Gas Flow Primary Standard
title_full_unstemmed Time-Correction Model Based on Diverter Speed for a pVTt Gas Flow Primary Standard
title_short Time-Correction Model Based on Diverter Speed for a pVTt Gas Flow Primary Standard
title_sort time correction model based on diverter speed for a pvtt gas flow primary standard
topic flow rate measurement
pVTt
time correction
diverter
url https://www.mdpi.com/1424-8220/22/11/4001
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