Radioactive measurements of flow intensity in the absence of complete tracer dilution

A list of the hitherto applicable flow rate measurement methods using the radioactive isotopes as tracers is presented. The rudiments of the single-sample-based method are discussed. The errors involved in the flow intensity measurement method with the use of tracers are theoretically reviewed, as dependent on the degree of commixture achieved. Further the results are presented of site measurements of flow intensity by the radioactive tracer technique in the case of incomplete commixture and dilution of the radioactive tracer - in order to assess a proper measurement technique for the resultant error to be corrected. Site measurements confirmed the substantial effect of the radioactive tracer commixture degree on the measured rate of flow intensity (24.5 per cent) as well as high incidence degree between the measurement results obtained by the radioactive tracer method and the tachymetric method using the current meter respectively (0.85 percent) in the cases when a correction parameter is entered for the incomplete tracer commixture in the flow volume. The conclusions from the reported investigations indicate that the tracer method of flow intensity measurement can be extended to cover the cases of incomplete tracer dilution in a flow. (author)