Atomization Characteristics of Energetic Liquid Film by Pulse Laser Reflection at Inclined Surface of High Refractive Index Material

摘要

Present work describes a novel laser-based procedure of the atomization of transparent energetic liquid materials. Although the phenomenon we have used is a simple laser ablation of liquid surface, one needs to irradiate the liquid surface from inside the liquid material. In this sense, the liquid materials should be a transparent material. The present procedure could work for all the transparent liquids including energetic materials. Pulse laser irradiation from outside the liquid medium leads to ablation phenomenon, only when the laser fluence is close to or larger than the breakdown threshold laser fluence of air. It is found that liquid surface ablation takes place for the laser fluence much less than air breakdown fluence. Whole processes were observed by pulse laser shadowgraphy with high-resolution film. Within the tested experimental conditions, minimum laser fluence for laser ablation at water-air interface is shown to be around 12-16 J/cm~2. We have tested several kinds of energetic liquid samples tested including ethanol, engine oil and kerosene, and their liquid atomization characteristics for the application to the ignition and/or initiation of bulk energetic liquid materials has been investigated. It is found that liquid atomization process is quite similar for several liquid samples, and all the energetic liquids tested can be ignited by a heated NiCr wire above the liquid surface.