HB-2彈體的空氣動力及熱傳模擬

Abstract

火箭飛行歷經次音速、穿音速、超音速至極超音速等不同的飛行階段。同時隨著高度的增加，大氣密度迅速降低，火箭也同時飛越連續體流域、過渡流域至稀薄流域。對火箭氣動力設計系統來說，克服各種不同的飛行環境所面對的氣動力問題是很重要的。本文研究重點為使用UNIC-UNS模擬HB-2彈體飛行在不同馬赫數和攻角下的空氣動力和熱傳情形。首先我們藉由網格測試去選出適當的網格大小，再使用該網格去模擬M=3.01和M=5.10時不同攻角的氣動力情形和M=9.59時的熱傳情形。在氣動力係數方面，M=3.01，Re=2.2E06，a=0~15時的氣動力結果：Ca=0.7，Cn=0~1.6，Cm=0~-1.4，Xcp/L=0.5~0.56。M=5.10，Re=2.5E06，a=0~15時的氣動力結果:Ca=0.7~0.9,Cn=0~1.4，Cm=0~-1.4，Xcp/L=0.52~0.56 。在熱傳情形方面，我們使用幾種不同的壁面溫度和流場模式去模擬，最終是較接近室溫的層流模式的熱傳分佈情形最為接近實驗的結果。而所得到結果的物理現象也都符合我們預估的。將結果和實驗的數據作比較，得出大部份的氣動力參數誤差都在4%以下，變化的趨勢也都和實驗的結果很吻合。這些結果都可以提供為後續研究人員的參考資料。

The rocket flies through various stages such as subsonic, sonic, supersonic, and hypersonic. Atmospheric density reduced rapidly with increasing of height, the rocket flies over the continuous flow, transitional flow, and rare flow at the same time too. To the aerodynamics force design system of the rocket, it is very important to overcome the aerodynamics problem that some kinds of flight environment cause. In this thesis, we apply a parallelized Navier-Stokes equation solver, named UNIC-UNS, to do the heat transfer and aerodynamics simulation of HB-2 model at different Mach numbers and attack angles of the flight. We make the grid convergence first to choose appropriate quality of grids. We do the aerodynamics simulation with the cases (M=3.01,M=5.10) with different angles of attack and the heat transfer simulation with the cases (M=9.59,Re=1.97E05 and Re=1.87E05) with the grid file. The results of aerodynamics coefficients at M=3.01 and Re=2.2E06 are Ca=0.7, Cn=0~1.6,Cm=0~-1.4,and Xcp/L=0.5~0.56. The results of aerodynamics coefficients at M=5.10 and Re=2.5E06 are Ca=0.7~0.9,Cn=0~-1.4,Cm=0~-1.4, and Xcp/L=0.52~0.56. In heat transfer simulation, we use some kinds of wall temperature and flow model. The results of comparison of non-dimensional heat flux distributions at and laminar flow are more accuracy then other cases. We get the results with physical phenomena as we know. We compare the results with experimental data. The error of most aerodynamics coefficients that we get is less than 4%. The tendency of coefficient’s change is also very similar to experimental data. The results and mesh can be reference material to supply the people of follow-up study.