Experimental study of jet surface structures and the influence of nozzle configuration

Under the three breakup regimes, the jet surface waves of different nozzles are captured and measured. The nozzles have different length to diameter ratios and contraction angles. The measured wavelengths are compared with the reported conclusions which were obtained by using spatial and temporal linear stability analysis. The results show that the jet wavelengths of different breakup regimes are covered by a single curve when the wavelengths are nondimensionalized with boundary layer thickness. For the nozzle with equal length and diameter, the entire translation section starts at Re=3×10 and ends at Re =4.5×10. The wavelength non-dimensionalized with boundary layer thickness is independent of nozzle configuration. The ratio of initial wavelength to boundary layer thickness ranges from 2 to 4.