摘要: |
模拟计算了一系列V型尾缘(Chevron)收敛喷管的详细涡结构(包括流向涡和展向涡)、引射系数、推力损失等性能,并与相关实验结果进行了对比验证。采用有限体积QUC IK格式和标准k-ε湍流模型,结合壁面函数求解雷诺平均的N-S方程。通过模拟计算与实验结果的对比,验证了计算方法的可行性。通过计算得出:V型尾缘喷管齿弯角越大,核心区长度越短,喷管出口下游的流向涡和展向涡的强度和尺度也越大。V型尾缘的齿弯角每增加1°,对应的喷管的堵塞比约增加0.98%,喷管的推力损失约增加1.71%,引射系数约增加3.45%。 |
关键词: V型尾缘+,强化混合+ 涡结构 推力损失 数值仿真 |
DOI: |
分类号:V235.131 |
基金项目:凡舟基金(200704056) |
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Numerical simulations on the flow fields downstream chevron nozzles |
LI Jing-xuan, WANG Fang, HUANG Yong, DENG Tian
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National Key Laboratory of Aircraft-Engines,Coll.of Energy and Power Engineering,Beijing Univ.of Aeronautics and Astronautics,Beijing 100083,China
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Abstract: |
Several chevron nozzles were numerical simulated.The vortex structure,entrainment ratio and thrust loss were analyzed.The QUICK and finite volume method,standard k-ε turbulence model,wall functions were employed to solve the N-S equations.The result shows that increasing chevron bend angle can enhance the fine-scale mixing,improve the initial axial velocity decay rate and increase the strength and the scale of the streamwise vortices and the slantwise vortices.When the bend angle increases by 1°,the block ratio is improved by 0.98%,the thrust loss is raised by 1.71% and the thrustper-mass-flux is improved by 3.45%. |
Key words: Chevron nozzles+ Enhancement of mixing+ Vortex structure Thrust loss Numerical analysis |