Sloppy tracer inputs

FINDING THE VESSEL E CURVE USING A SLOPPY TRACER INPUT... 

Sloppy Tracer Inputs It is not alw s possible to inject a tracer pulse cleanly as an input to a system, owing to the fact that it takes a finite time to inject the tracer. When the injection does not approach a perfect pulse input (Figure 14-10), the differences in the variances between the input and output tracer measurements are used to calculate the Peclet number ... 

Sloppy Tracer Inputs 970 Tanks-in-Series Model Versus Dispersion Mode 974 Numerical Solutions to Flows with Dispersion... 

Suppose we measure the sloppy input and output tracer curves for a process vessel for the purpose of studying the flow through the vessel, thus to find the E curve for the vessel. In general this requires deconvolution (see Chapter 11) however, if we have a flow model in mind whose parameter has a one-to-one relationship with its variance, then we can use a very simple shortcut to find the E curve for the vessel. 

The sharpest way of experimentally distinguishing between models comes by noting how a pulse or sloppy input pulse of tracer spreads as it moves downstream in a flow channel. For example, consider the flow, as shown in Fig. 15.4. The dispersion or tanks-in-series models are both stochastic models thus, from Eq. 13.8 or Eq. 14.3 we see that the variance grows linearly with distance or... 

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