摘要本文采用数值模拟的方法，对某火箭弹在管内发射过程，燃气射流在定向器内部流动情况进行研究。研究了Gambit中，计算区域的设定，网格的布置以及边界条件的预处理问题，并在fluent中通过定义边界条件，动网格技术以及用户自定义函数，实现了二文轴对称模型在整个运动状态下的模拟。
在已经建立好的二文轴对称网格模型的基础上，讨论研究了网格大小，燃气粘度，以及湍流模型对于本次计算结果的影响，通过这些探究，选择了合适的的参数进行毕业设计的仿真。通过分析比较稳定自由射流场，以及火箭发动机运动过程中不同位置的燃气射流参数，对于燃气射流所遵循的的气体动力学有了进一步了解，并且给出了管内气体静温，静压，气体马赫数，以及壁面粘性力等所关心的参数。 通过以上研究及相关结论，不仅使我对于气体动力学有了进一步了解，也为定向器的优化提供研究数据。28417
关键词： 燃气射流 动网格 自由射流 管内非定常流动
毕业论文设计说明书外文摘要
Title Numerical simulation of unsteady flow in Two-dimensional Axis-symmetric Model of the directional device
Abstract
The thesis adopted numerical simulation to study the flow of gas jet in the directional device when launching a rocket weapon system.
The thesis researched the setting of the computational area,the layout of the mesh and the parameters of the boundary conditions in Gambit. By defining the boundary conditions,the dynamic mesh technology and the user-defined function,the simulation of the two-dimensional axis-symmetric model is realized in the fluent.
Based on the established 2D axis-symmetric graphics,the effect of mesh size, gas viscosity, and turbulence model on the results of this calculation is discussed. Through these researches, the simulation of the appropriate parameters chosen for the graduation design model. For gas jet followed by the aerodynamics to have a further understanding,by the analysis and comparison with the stable free jet field, the gas jet parameters of different position in the process of the rocket motor.and also get the parameters of the temperature, static temperature pressure, gas Mach number, and wall viscosity of the tube.
Through the above research and related conclusions, it not only makes me have a further understanding of gas dynamics, but also provides the research data for the optimization of the directional device.
Key words：gas jet，dynamic mesh，free flow ，unsteady flow inside tube
目 次
1 引言 1
1.1 研究背景及意义 1
1.1.1 研究背景 1
1.1.2 研究意义 1
1.2燃气射流研究发展 2
1.3 本文研究内容 3
2 射流数学模型以及网格生成 4
2.1 燃气射流基本控制方程 4
2.1.1 质量守恒定律 4
2.1.2 动量守恒定律 4
2.1.3 能量守恒方程 5 定向器内二维轴对称模型的非定常流动模型:http://www.751com.cn/jixie/lunwen_23253.html