火箭发动机喷管中流固耦合的力学行为及其影响

项目名称： 火箭发动机喷管中流固耦合的力学行为及其影响

项目编号： No.11272262

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 叶正寅

作者单位： 西北工业大学

项目金额： 90万元

中文摘要： 火箭发动机启动和关闭过程中内部气流总压会有变化，还会面临从地面到高空的不同外部环境，尤其还存在地面试验环境的情况，而发动机喷管外形的设计不可能包括这些变化，因此发动机喷管会面临喷管气流过膨胀和气流分离的状况，它会引起喷管的侧向载荷，是火箭发动机使用和地面试验过程中的巨大威胁。尽管经历几十年来的不断研究，仍然对喷管非对称分离导致的侧向载荷机理没有认识清楚，通过对国外已有工作的分析，发现喷管流固耦合的动力学过程会对喷管侧向载荷有很大的影响，本项目从喷管流固耦合的精确数值模拟出发，建立一套发动机喷管流固耦合的模拟方法，更全面、真实再现发动机喷管的实际工作环境，研究在不同内部总压、不同外部环境下喷管的流固耦合动力学特征，分析和揭示该动力学过程对喷管内流场激波系结构、激波/附面层干扰、非对称分离涡的影响机制，从而认识和理解喷管流固耦合过程对侧向载荷形成的影响机理。此工作对航天科技发展具有较大意义。

中文关键词： 喷管；流固耦合；数值方法；侧向力；

英文摘要： During rocket engine start-up and shut-down, the feeding pressure changes to a large extent. The rocket nozzles must experience ambient environment from sea-level to high altitude, also the sea-level environment in ground test. The nozzle designed cannot work well for all these situations. Therefore, transient over-expansion and internal flow separation will certainly appear. This phenomenon causes an asymmetric pressure distribution which can result in side loads and induce dynamic loads. These side loads are of a large enough magnitude to damage the nozzle itself as well as engine support structures. Though the problem of flow separation induced side loads has investigated for decades. The mechanics and the affecting parameters which result in the asymmetric separated flow in the nozzle have not been understood yet. By analyzing the computation approaches in the literatures published in recent years, the fluid/structure interaction play an important role in the side loads generation. In present project, a numerical method for simulating the nozzle fluid/structure interaction will be established. The actual and more detailed ambient environments will be considered and involved. The characteristics of fluid/structure interaction under different feeding pressure and different ambient environment parameters will b

英文关键词： nozzle；fluid-structure interaction；numerical methods；side loads；