Abstract Spray of cryogenic fluids, which involves complicated aerodynamic instability and superheat flashing, is receiving increasing attention in cryogenic cooling applications and cryogenic propellant ignition. In the present study, a two-fluid numerical model coupling the Algebraic Interfacial Area Density (AIAD) model and Homogeneous Relaxation Model (HRM) framework was built to investigate the underlying physics of liquid nitrogen (LN2) spray. The proposed approach aims at describing the underlying physics affected by both aerodynamic and flashing dynamics. Behaviors of spray characteristics, including flow regime, pressure distribution, velocity distribution and intact core length, are analyzed subsequently. Accordingly, effects of aerodynamic instability and flashing on the LN2 spray were analyzed. Finally, a modified correlation of liquid-intact-core length which involves both of the aerodynamic and thermodynamic effects was proposed and the weight of two effects were evaluated accordingly.

中文翻译：

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液氮喷雾特性数值分析

摘要 低温流体喷雾涉及复杂的空气动力学不稳定性和过热闪蒸，在低温冷却应用和低温推进剂点火中越来越受到关注。在本研究中，建立了一个耦合代数界面面积密度 (AIAD) 模型和均匀松弛模型 (HRM) 框架的双流体数值模型，以研究液氮 (LN2) 喷雾的基础物理。所提出的方法旨在描述受空气动力学和闪光动力学影响的基础物理。随后分析了喷雾特性的行为，包括流态、压力分布、速度分布和完整核心长度。因此，分析了空气动力不稳定性和闪蒸对 LN2 喷雾的影响。最后，