横向剪切气流中气液两相环状流射流液膜的破碎与雾化

射流掺混在民用及国防等领域具有重大应用需求。气动剪切作用可增强射流液体的不稳定，促进液体的破碎与雾化。基于这一原理，本项目提出了采用气液两相环状流射流与横向气流掺混这一创新思路。环状流射流不同于传统的射流方式，横向气流环境中，受内侧剪切气流与外侧横向气流共同作用，液膜更容易发生破碎与雾化，从而实现与横向气流的高效掺混。横向剪切气流中环状流射流液膜的破碎与雾化呈现高度非定常特性与复杂的相界面结构。通过机理实验和理论分析相结合，获得横向剪切气流中环状流射流液膜的变形、破碎与雾化基本规律，查清液膜破碎机制和临界破碎动力学条件、流场中涡结构及其对液膜破碎与雾化的影响机制，揭示横向剪切气流中环状流射流液膜的破碎与雾化机理，掌握环状流射流与横向剪切气流相互作用的系统规律。本项目拓宽了射流掺混研究领域，为相关行业应用环状流射流与横向气流高效掺混组织提供了理论支撑，具有重要的学术价值和应用前景。

The jet mixing has been extensively applied in military and civil fields. The aerodynamic forces can intensify the instability of the liquid jet and promote the breakup and atomization. Based on this, a novel mixing technique is proposed by injecting the gas-liquid annular flow jet into the crossflow. In the mutual influence of both inside gas flow and outside crossflow, the instability of the liquid sheet of the annular flow jet is intensified and the breakup and atomization are promoted effectively, and hence an efficient mixing between the gas-liquid annular flow jet and the crossflow can be achieved. The breakup and atomization of the liquid film of the annular flow jet are significantly different from that of other forms of liquid jet in the mutual influence of both inside gas flow and outside crossflow. In the crossflow, the breakup and atomization of the liquid sheet of the gas-liquid annular flow jet is a complex nonlinear and dynamic process and has complex phase interface structures. Through analytical and experimental methods, the project is to obtain the breakup and atomization characteristics of the liquid sheet of annular flow jet in crossflow, and to illustrate the breakup mechanisms and the critical breakup dynamic conditions of the liquid sheet. Studies on the formation and development of the vortices induced by the interaction of the gas-liquid annular flow and the crossflow, as well as the influence mechanism of the vortices on the breakup and atomization of the liquid sheet will also be included. A better knowledge of the dynamic interaction between the gas-liquid annular flow jet and the crossflow will be obtained. This project achievements will expand the research field of jet mixing, and will benefit in relevant applications of the mixing enhancement between the gas-liquid annular flow jet and the crossflow. Research results show great academic significance and applicable potential.