État actuel des méthodes de dilution pour la mesure des débits dans les conduites en charge

E.D.F., Direction des Etudes et Recherches, Chatou.

Résumé

The radio-active tracer method (one of the three in general used today) has become increasingly popular since the advent of radio-active solution generators. Research in this field of recent years has produced a lot of data which it has become urgent to synthesize. Mathematical proofs are supplied for the following : (i) Movement of the radio-active "c1oud's" centre of gravity at the average flow velocity. (ii) The existence of a systematic measurement error depending on homogeneity of the mixture. (iii) The definition of mixing distance beyond which the mixture in a cross-section is homogeneous. (iv) Methods of estimating the mixing distance. This method needs special equipment for its application, the main components of which are the radio-element generator, the injection and detection systems and recording and data-abstracting arrangements. The method is briefly described, with results obtained in various-sized pipes.