Experimental Investigation on Break-Up Process of Planar Liquid Jet Film
平面液体层碎裂过程实验研究

Planar water film was jetted into a stationary air medium with unequal velocity air streams on both sides from a small aspect ratio nozzle. The break-up process of planar water jet film was experimentally studied. Results show that the waveform of water film surface wave is symmetrical, and the length of break-up water jet segment is longer along with the liquid jet Reynolds number increases. Jet pressure has no direct influence on break-up length. Phase difference between upper and bottom gas-liquid interface of planar jet film is formed by air assistant. The length of water film break-up segment decreases along with air stream velocity increases. This indicates that air assistant may strongly promote break-up of water jet with lower Reynolds number. The effect of air assistant on water film break-up length is weak for water jet with larger Reynolds number. Liquid film remains stable for long time, and liquid film rip phenomenon did not appear even for high velocity air assistant. It is presented that high Reynolds number of liquid jet is a stable factor for Rayleigh mode jet from small aspect ration nozzle. Comparing with some dimensionless parameters, such as gas-liquid velocities ratio and Mach number, Reynolds number is a main influence factor for liquid jet break-up process.