Enabling off-design linearised aerodynamics analysis using Krylov subspace recycling technique
Enabling off-design linearised aerodynamics analysis using Krylov subspace recycling technique
复制标题
使用 Krylov 子空间回收技术实现非设计线性空气动力学分析
DOI：
10.1016/j.compfluid.2016.10.018
复制
发表时间：
2016
影响因子：
2.8
通讯作者：
K. Badcock
中科院分区：
文献类型：
--
作者：
Shenren Xu;S. Timme;K. Badcock
当使用频域线性化计算流体动力学来分析飞机颤振、阵风响应或冲击冲击等气动弹性问题时，主要的计算挑战是解决大型稀疏线性方程组需要过多的内存和CPU时间。为了解决广义最小残差线性方程解算器存在的这些问题，本文采用了带压缩重启的广义共轭残差解算器，其中在求解单个线性频域问题的重启之间循环一个不变的Krylov子空间，并在改变系统矩阵和强制项时循环求解一系列方程。该方法在工业规范中得到了实现，并应用于俯倾翼型的强制激励和颤振开始、现实客机的无粘跨声速流动和一般半翼身模型在预颤振条件下的三个测试用例。所调查的问题的内存需求最多减少了一个数量级，而CPU时间最多减少了三倍。
The major computational challenge, when using frequency domain linearised computational fluid dynamics in the analysis of aeroelastic problems such as aircraft flutter, gust response or shock buffet, are the excessive memory and CPU time requirements to solve the large sparse linear systems of equations. To address these issues found with the generalised minimal residual linear equation solver, the generalised conjugate residual solver with deflated restarting is adopted here in which an invariant Krylov subspace is recycled both between restarts when solving a single linear frequency domain problem and for a sequence of equations when varying the system matrix and forcing terms. The proposed method is implemented in an industrial code and applied to three test cases including the forced excitation and buffet onset of a pitch-plunge aerofoil, a realistic passenger aircraft in inviscid transonic flow and a generic half wing-body model at a pre-buffet condition. The memory requirements for the problems investigated are reduced by up to an order of magnitude, while the CPU times are reduced by up to a factor of three.