NTERNATI0NAL STANDARD (ISO 2975/II Measurementofwaterflowinclosedconduits- Tracer methods - Part Il : Constant rate injection method using non-radioactive tracers Mesurede debit de I'eau dans les conduites fermees-Methodes partraceurs- Partie ll: Methode d'injection a debit constant,utilisant des traceurs non radio-actifs First edition-1975-08-15 TSO 2975/I-1975 (E) UDC681.121.84 Ref.No.ISO2975/II-1975 (E) Descriptors: flow measurement, pipe flow, water flow, tracer method, non-radioactive tracers, testing conditions,,colorimetric analysis, fluorimetric analysis, conductimetric analysis, error analysis. Price based on 9 pages FOREWORD ISo (the International Organization for Standardization) is a worldwide federation of national standards institutes (ISO Member Bodies). The work of developing International Standards is carried out through ISO Technical Committees. Every Member Body interested in a subject for which a Technical Committee has been set up has the right to be represented on that Committee. International organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. Draft International Standards adopted by the Technical Committees are circulated to the Member Bodies for approval before their acceptance as International Standards by the iso Council. International Standard ISO 2975/Il was drawn up by Technical Committee ISO/Tc 30,Measurement of fluid flow in closed conduits,and circulated to the Member Bodies in May 1974. It has been approved by the Member Bodies of the following countries : Australia Ireland Thailand Belgium Mexico Turkey Bulgaria Netherlands United Kingdom Czechoslovakia Romania U.S.A. France Spain U.S.S.R. Germany Switzerland No Member Body expressed disapproval of the document. International Organization for Standardization, 1975 Printed in Switzerland INTERNATIONALSTANDARD ISO2975/II-1975 (E) Measurement of water flow in closed conduits- Tracermethods- Part Il : Constant rate injection method using non-radioactive tracers O INTRODUCTION where Co is the initial concentration in the stream which is flowing at the rate Q. This International Standard is the second of a series of standards covering tracer methodsof water flow Hence : measurement in closed conduits. The complete series of standards will be as follows : Part/: General. using Generally C1 is much greater than C2which leads to a Part /l: Constantrate injection method simplification ofequation (1)as follows : non-radioactive tracers. Part lll:Constant rate injection method using radioactive tracers. Part/V:Integration (sudden injection) method When C2 is much greater than Co, the equation can be using non-radioactive tracers. reduced still further to Part V: Integration (sudden injection)method using =0 radioactive tracers. Part VI: Transit time method using non-radioactive Flow rate Q can thus be determined by comparing the tracers. concentration of the injected solution with the Part Vll: Transit time method using radioactive concentration of samples removed from the conduit. tracers. In order to increase the accuracy it is recommended that the standard solution be prepared to a given dilution ratio Nstwhichshallbeapproximatelyequivalenttothedilution ratio N which is expected in the sample takenfrom the measuring cross-section. 1SCOPEANDFIELDOFAPPLICATION The standard solutions and the samples taken from the This International Standard specifies the constant rate measuring cross-section shall be compared using identical injection method using non-radioactive tracers for the methods, and the following formula is applicable : measurement of water flow rate in closed conduits. N The flow rate to be determined can be found from the 2 PRINCIPLE formula Flowrate measurement bya constant rate injection method Q=qmNst isbasedonacomparisonbetweentheconcentrationC,of a tracer,continuously introduced witha knownvolume rate of flowq,and the concentration of samples.C2 taken 3REQUIREDCONDITIONS at some place beyon