Instability of micro jet impinging onto a pool

A micro liquid jet discharged into a downstream pool exhibits different instabilities at certain heights. For some nozzle heights, the water jet shows a steady wavy profile while for some other heights, the water jet oscillates around the nozzle axis at given frequency. A series of experiments are conducted to identify the regimes of jet state with respect to nozzle heights, Reynolds numbers and Weber numbers. For the oscillation regime, oscillating characteristics of the jet are investigated in terms of different liquid properties. A simple model is developed to describe and explain the phenomena.