Investigation of turbulent flows via pseudo flow visualization. I: Axisymmetric jet mixing layer

Hot-wire anemometcr measurements obtained in the near-field axisymmetric jet mixing layer by Glauser and George (1987) are examined using a pseudo flow visualization (PFV) technique. Pseudo flow visualization is a visualization procedure used to manipulate data obtained from an array of probes to create a graphical representation of the instantaneous and fluctuating velocity components of a flow field. An indicator function was employed to identify the frequency content of each velocity-time trace, giving insight into the analysis of the visualizations. From this application, the natural shedding frequency, or preferred mode, of the large-scale structures was determined and compared with the conventional streamwise and radial spectral measurements acquired by Glauser and George. The wavelength of the preferred mode, nondimensionalized by the jet exit diameter, was determined to be approximately 2.4. The technique is developed and discussed for the fundamental and fairly well-researched mixing layer of the axisymmetric jet. Our aim is to verify the effectiveness of PFV in the context of a well-documented flow. (Author)