液氧管路燃气射流冷凝压力脉动传播特性研究  

Propagation Characteristics of Pressure Pulsation in Jet Condensing Flow of Liquid Oxygen Feed System

作　　者：李翠[1] 武定航 杜飞平 李晨烁 厉彦忠[1,3] LI Cui;WU Dinghang;DU Feiping;LI Chenshuo;LI Yanzhong(School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China;Science and Technology on Liquid Rocket Engine Laboratory, Xi’an Aerospace Propulsion Institute, Xi’an 710100, China;State Key Laboratory of Technologies in Space Cryogenic Propellants, Beijing 100028, China)

机构地区：[1]西安交通大学能源与动力工程学院,西安710049 [2]西安航天动力研究所液体火箭发动机技术重点实验室,西安710100 [3]航天低温推进剂技术国家重点实验室,北京100028

出　　处：《西安交通大学学报》2022年第7期127-135,共9页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(52176021);航天低温推进剂技术国家重点实验室开放研究课题资助项目(SKLTSCP202012)。

摘　　要：针对液氧/煤油补燃循环发动机液氧管路中,因发动机不稳定燃烧、系统结构振动、阀门启闭等原因产生压力脉动,从而影响推进剂流动及相间传热传质的问题,基于欧拉两流体模型构建了低温两相流动冷凝压力脉动传播数值模型,运用计算流体动力学(CFD)模拟研究了压力脉冲传播下气氧-液氧大温差掺混冷凝的两相流场瞬态分布特性及其松弛特性,分析了压力脉冲极性、幅值和持续时间对流场松弛时间、脉动传播速度和衰减率等传播特性的影响规律。模型预测结果与前人实验数据呈现良好的一致性。计算结果表明:相比于稳定冷凝状态,幅值为100 kPa、持续时间为0.1 s的正压力脉冲使气相冷凝长度缩短9.3%,相同参数的负压力脉冲则使其相对延长7%。正脉冲幅值的增加使得其平均传播波速增大、衰减率减小,负压力脉冲则相反;波速和衰减率与脉冲持续时间呈负相关性,随脉冲持续时间由0.01 s增长至1 s,正、负压力脉冲平均波速减小约65%,平均衰减率分别减小约51%和90%;松弛时间随脉冲幅值、持续时间的增加均增加,对脉冲极性的依赖性很小。该计算结果可为液氧/煤油补燃循环发动机推进系统动特性分析提供有效依据,为提升低温液体火箭安全性和稳定性提供一定的参考。Propagation of pressure fluctuation in propellant pipeline plays an important role in liquid rocket safety due to its effect on the flow and interphase heat and mass transfer.In the present study,a numerical model was developed based on the Eulerian two-fluid method to investigate the propagation characteristics of pressure pulsation in cryogenic two-phase flow condensation.CFD simulation was used to investigate transient distribution characteristics and relaxation characteristics of two-phase flow field under the conditions of large temperature difference between gaseous oxygen and liquid oxygen and their mixture condensation,and analyze the effects of the polarity,amplitude and duration of pressure pulse on such propagation characteristics of flow field as relaxation time,pulsation propagation speed and attenuation rate.The results show that the condensation flow region expands by about 7%due to negative pressure pulses with an amplitude of 100 kPa and a duration of 0.1 s,but shortens by about 9.3%due to the positive ones.At the fixed flow conditions,the increase of the positive pulse amplitude leads to an increase in its propagation velocity and a decrease in the attenuation rate,while the negative pressure pulse exhibits an opposite characteristic.As the duration of the pressure pulse increases from 0.01 s to 1 s,the average velocity decreases by about 65%for both the positive and negative pressure pulses,while the attenuation rate decreases by about 51%for the positive pressure pulse and 90%for the negative one,respectively.The relaxation time shows little dependence on the polarity of pressure pulse,but increases with the increases of pulse amplitude and duration.The calculation results can provide an effective basis for the analysis of the dynamic characteristics of the cryogenic rocket engine propulsion system,which is of great significance for improving the safety and stability of cryogenic liquid rockets.

关 键 词：低温液体火箭 两相流动冷凝 压力脉动 传播特性 计算流体动力学模拟 

分 类 号：TB613[一般工业技术—制冷工程]