Discrete values of the large scale structure in turbulent flows
The time average of the amplitude of a single intermittency signal in a free jet was measured. Two different methods of measurements were used: the instant integration of a single signal (intermittency detector and instant integrator) and the pattern recognition method based on the evaluation of a certain number of similar signals (sampling of an ensemble of digitized signals with a similar distribution of amplitude). The measurements, taken at random times and analysed by two different techniques show a special type of a distribution function. The distribution shows discrete values for different flow velocities and different nozzle diameters indicating the existence of eigenvalues in the flow.
KeywordsLarge Scale Structure Random Time Nozzle Diameter Vortex System Pattern Recognition Method
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