基于自适应修正模型的飞行器外流场三维计算方法
Adaptive Modification Turbulence Model for Flow Field of Aircraft Calculating in Three Dimensions
彭革 1徐兴贵 2李忠武 2任维贺 3李康 3郑国宪 3邓红艳3
作者信息
- 1. 保山学院大数据学院 云南保山 678000
- 2. 云南财经大学信息学院 昆明 650221
- 3. 北京空间机电研究所 北京 100081
- 折叠
摘要
目前飞行器外流场仿真方法中存在流体可压缩性判断依赖经验知识以及目标外流场三维仿真缺乏封闭约束条件的问题.对此,提出一种基于自适应修正模型的三维外流场数值计算方法.根据飞行器外流场变异系数先验知识,采用加权平均N-S方程表示可压缩流体物理量分布,同时利用膨胀压缩修正和激波不定项修正两种策略自适应地修正k-ε湍流模型的可压缩性约束条件,并采用壁面函数对近壁区进行近似计算修正约束条件.以某型号无人机外流场分布三维建模仿真实验,结果表明:当飞行器速度达到1.5马赫时,可压缩修正模型出现边界约束条件临界值,所提自适应可压缩修正算法能有效判断气体可压缩性的变化并提升流体分布计算的准确性.
Abstract
In view of the problems of fluid compressibility judgment relying on empirical knowledge and the lack of confinement constraints in the current three-dimensional simulation methods for vehicle outer flow field,an adaptive modification turbulence calculating model for the three dimensions vehicle outer flow field is proposed.The proposed algorithm adopts the density-weigh-ted average N-S equation to calculate the flow field distribution of the compressible fluid according to the a priori knowledge of the coefficient of variation of the vehicle outer flow field,and utilizes two strategies,namely,expansion-compression modification and surge indeterminate modification to modify the compressibility constraints of the k-ε turbulence model in an adaptive way,and uses the wall function to modify the constraints in the near-wall region in an approximate computation.Experimental results of three-dimensional modeling and visualization of the outer flow field distribution of a certain type of unmanned aerial vehicle(UAV)show that when the Mach value reaches 1.5,the compressibility modification algorithm produces effects obviously.The proposed adaptive compressibility modification model is able to effectively judge the change of gas compressibility and improve the accuracy of fluid distribution calculation.
关键词
湍流/流场三维仿真/密度加权平均数值模拟/可压缩修正Key words
Turbulence/3D simulation of outer flow field/Density-weighted averaged numerical simulation method/Compressibility correction引用本文复制引用
基金项目
国家自然科学基金地区科学基金(62161051)
云南省教育厅科研项目(2023J0678)
云南省科技厅科技项目(202101BA070001-016)
云南省服务计算重点实验室开放基金(YNSC23119)
出版年
2024
NETL
NSTL
万方数据