Abstract:
This paper presents an experimental study on the evolution of charged ethanol atomization modes and the instability of the micro-jet. Based on the high-speed microscopy and small scale PIV technology, the microstructure evolution process of the charged ethanol micro-jet was accurately captured, the jet instability evolution characteristics of different atomization models and its influence on atomization characteristics under the effect of the electrical Bond number were discussed. The results show that the jet's non-axisymmetric radial disturbance occurs throughout the jet atomization models. As the electrical Bond number increases, the jet flow deviation increases first and decreases subsequently. The uncertainty fluctuation range gradually increases in the cone jet mode, while it gradually narrows down to zero and increases again in the multi-jet mode. The jet core and its velocity direction of the cone-jet mode all deviate from the axis, and the jet speed significantly declines compared with the spindle mode. The velocity of the jet core obviously rises when the jet transits to the multi-jet mode, while the velocity distribution has many differences at different electrical Bond numbers. The jet boundary streamline shows disorder and lack of symmetry most of the time. However, a stable multi-jet mode with a peak velocity occurs for a very short interval of the electrical Bond number.