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The turbulent jet with two sinusoidal nozzle exit configurations of in-phase and 180o out-ofphase was investigated experimentally using a smoke-wire method and a hot-wire anemometry. Mean velocity and turbulence intensity were measured at several downstream locations under ReD = 5000. For the case of in-phase nozzle configuration, the length of potential core exhibits negligible difference with respect to the transverse locations (0, λ/4 and λ/2), similar to those of a plane jet. On the other hand, a maximum difference of 30% in the potential-core length occurs for the 180o out-of-phase configuration. The spatial distributions of turbulence intensities also shows significant difference for the nozzle of 180˚ out-of-phase, whereas non-symmetric distribution is observed in the near-exit region(x/D = 1) for the inphase sinusoidal nozzle jet. Compared to normal slit jet, the sinusoidal nozzle jets seem to suppress the velocity deficit as the flow goes downstream. The sinusoidal nozzle jet was formed to decrease turbulent intensity dramatically. The flow visualization results show that the flow characteristics of the sinusoidal nozzle jet are quite different from those of the normal slit plane jet.


The turbulent jet with two sinusoidal nozzle exit configurations of in-phase and 180o out-ofphase was investigated experimentally using a smoke-wire method and a hot-wire anemometry. Mean velocity and turbulence intensity were measured at several downstream locations under ReD = 5000. For the case of in-phase nozzle configuration, the length of potential core exhibits negligible difference with respect to the transverse locations (0, λ/4 and λ/2), similar to those of a plane jet. On the other hand, a maximum difference of 30% in the potential-core length occurs for the 180o out-of-phase configuration. The spatial distributions of turbulence intensities also shows significant difference for the nozzle of 180˚ out-of-phase, whereas non-symmetric distribution is observed in the near-exit region(x/D = 1) for the inphase sinusoidal nozzle jet. Compared to normal slit jet, the sinusoidal nozzle jets seem to suppress the velocity deficit as the flow goes downstream. The sinusoidal nozzle jet was formed to decrease turbulent intensity dramatically. The flow visualization results show that the flow characteristics of the sinusoidal nozzle jet are quite different from those of the normal slit plane jet.