Wu Xuecheng, Lin Wenhui, Wang Lei, Song Ge, Wu Yingchun
Appl Opt. 2021 Feb 1;60(4):A131-A139. doi: 10.1364/AO.404322.
Atomization of low temperature fuel is of great importance in a jet engine combustor, and its visualization and diagnostics are challenging, especially in the presence of shreds and ligaments. A 25 kHz picosecond pulsed digital inline holography system is applied to measure the spray produced by an airblast atomizer with low temperature kerosene. The breakup process of shreds and ligaments of -37 kerosene are visualized and analyzed, revealing the transition of liquid jet disintegrating into droplets under the atomizing air film. Three-dimensional positions and size distributions of droplets in spray are acquired. It is found that a decrease in the kerosene temperature increases shreds and ligaments in the spray, which eventually leads to reduction of droplet density and increase of droplet size, while increasing the air pressure can compensate the degradation. This work also demonstrates that high speed holographic imaging is a powerful tool in spray diagnostics and liquid breakup visualization.
低温燃料的雾化在喷气发动机燃烧室中至关重要，其可视化和诊断颇具挑战性，尤其是在存在碎片和液柱的情况下。应用一台25千赫兹的皮秒脉冲数字在线全息术系统来测量由低温煤油的空气雾化喷嘴产生的喷雾。对-37煤油的碎片和液柱的破碎过程进行了可视化和分析，揭示了在雾化气膜作用下液体射流破碎成液滴的转变过程。获取了喷雾中液滴的三维位置和尺寸分布。研究发现，煤油温度降低会增加喷雾中的碎片和液柱，最终导致液滴密度降低和液滴尺寸增大，而增加气压可以弥补这种恶化。这项工作还表明，高速全息成像在喷雾诊断和液体破碎可视化方面是一种强大的工具。
