Application of Frequency-Response Techniques to Analysis of Turbulent Diffusion Phenomena

Pulse testing can be used to describe mixing phenomena. This technique yields frequency-domain information and can accept an arbitrary input. It requires the recording of the input and output pulses and their reduction, by Fourier analysis, to frequency-domain information. A digital computer is used for the data reduction. Two solutions of the equation describing simultaneous mass transport of dissolved or suspended matter are given. One of these is applicable when both input and output concentrations are measured in a pipe and represents a frequency-domain equation. A procedure using the integral of squared error as a measure of deviation also is described. In experiments, the model gave a nearly perfect representation of the phenomenon at high Reynolds numbers.