A droplet/wall impact model and simulation of a bipropellant rocket engine
A droplet/wall impact model and simulation of a bipropellant rocket engine
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DOI：
10.1016/j.ast.2019.03.018
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发表时间：
2019-05
影响因子：
5.6
通讯作者：
Pengfei Fu;Lingyun Hou;Z. Ren;Zhen Zhang;Xiaofang Mao;Yusong Yu
中科院分区：
文献类型：
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作者：
Pengfei Fu;Lingyun Hou;Z. Ren;Zhen Zhang;Xiaofang Mao;Yusong Yu
液滴撞击固体壁有助于液滴在内壁上蒸发和冷却。根据实验数据建立了一个新的液滴/壁面碰撞模型，该模型同时考虑了液滴的运动学参数和壁面的热力学参数。该模型描述了撞击后液滴的行为，并确定了五种代表性的状态，即，粘附/扩散、悬浮、回弹、沸腾（包括破裂）和飞溅，通过液滴的临界韦伯数和壁温。为了评估新的模型，进行了数值模拟的推进剂液滴撞击壁的双组元火箭发动机燃烧室。与实验数据的比较表明，更好的预测室的壁温比从以前的模型。大量的大尺寸的单甲基肼和四氧化二氮液滴在沸腾诱导破碎和飞溅制度打破成更小的液滴时，使用新的模型。在弹着点和喉部附近也有温度峰值。特别是在燃烧室的喉部，新模型准确地预测了壁面温度分布，提供了改进的燃烧室预测和评估喉部的热保护。
Droplet impact on a solid wall contributes to droplet vaporization and cooling on the inner wall. A new droplet/wall impact model is developed and fitted from the experimental data, which takes both kinematic parameters of the impinging droplets and thermal parameters of the solid wall into consideration. The model describes the behavior of droplets after impact and identifies five representative regimes, i.e., stick/spread, suspend, rebound, boiling including breakup, and splash, through the critical Weber number of droplets and wall temperature. To assess the new model, numerical simulations were performed of propellant droplets impacting the wall of a bipropellant rocket engine chamber. A comparison with experimental data shows better predictions of the wall temperature of the chamber than obtained from previous models. A larger number of large-sized monomethylhydrazine and nitrogen tetroxide droplets in the boiling induced breakup and splash regimes break into smaller droplets when using the new model. There are also temperature peaks near the impact points and near the throat. Especially in the throat of the combustion chamber, the new model predicts the wall temperature distribution accurately, offering improved prediction of the combustion chamber and assessing thermal protection of the throat.