Fluid dispersion-generalization and comparison of mathematical models—I generalization of models

Abstract Many models have been used to characterize dispersion of fluids in flowing systems. Some account for both transverse and longitudinal dispersion, while others account for longitudinal dispersion alone. In addition, the variety of experimental tracer methods used to find the parameters of the models makes the resultant analyses seemingly unrelated. We show here the relationship between these models and generalize all the previously presented measurement techniques. This gives a comprehensive picture of the field of dispersion, allows a quantitative evaluation of the error incurred when a simple model is used in place of a more exact but more unwieldy model, and gives future experimenters the necessary information to decide what combination of experimental set-up and mathematical model yields, within prescribed limits of error, an analysis of desired accuracy.