Theory Of Tracer Flow
Authors: Bischoff K.B. , Ellington R.T. , Uhl A.E. , Worcester D.A. 
Published: December 2007

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This paper is to be presented at the 38th Annual Fall Meeting of the Society of Petroleum Engineers of AIME in New Orleans, Louisiana, on October 6–9, 1963 and is considered the property of the Society of Petroleum Engineers. Permission to publish is hereby restricted to an abstract of not more than 300 words, with no illustrations, unless the paper is specifically released to the press by the Editor of JOURNAL OF PETROLEUM TECHNOLOGY or the Executive Secretary. Such abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in JOURNAL OF PETROLEUM TECHNOLOGY or SOCIETY OF PETROLEUM ENGINEERS JOURNAL is granted on request, providing proper credit is given that publication and the original presentation of the paper.
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Abstract
An analysis of the theory of the dispersion of tracers in flowing streams reveals fundamental inconsistencies in the general classic developments and a lack of correlation between theory and measured behavior. Additionally, most classic and more-recent developments fail to adequately account for the behavior of tracers in natural gas flowing turbulently in a pipeline. A model for tracer flow is proposed which accounts for both molecular diffusion and turbulent mixing. Application of this model to actual field test data indicates correlation within the statistical certainty of the test data measurements.

Introduction

History
The use of tracers to investigate various aspects of fluid flow dates from the colored filament experiments of Reynolds. At that time, colored dyes were often used to trace flow patterns in open channels. Similar experiments on flow in conduits date from the beginning of the present century. In the expanding use and application of tracers, many different properties have been utilized: electrical and thermal conductivity, density, chemical reaction, radioactivity, and visual effects.
Among the investigators who early used tracers in pipes were Allen and E. A. Taylor, who used salt as a tracer in flowing water. Griffiths reported good qualitative results in following flow currents with dye-tagged water flowing through glass tubes. G. Taylor carried out one of the most important investigations in the field when he traced the movement of permaganate dye in laminarly flowing water and brine in turbulently flowing water.
Since World War II several new techniques have been developed, and radio-active tracers have come into use. Tracers are now used to tag the interfaces between different batches in product pipelines, and different crude grades in gathering and transmission systems. Flow patterns in petroleum reservoirs have been traced with helium and radioactive gases. Some tests have been carried out on refinery gas lines with hydrogen as the tracer. More recently, the use of radioactive tracers has been extended into many other fields.