Comparative study of inner–outer Krylov solvers for linear systems in structured and high-order unstructured CFD problems
نویسندگان
چکیده
Advanced Krylov subspace methods are investigated for the solution of large sparse linear systems arising from stiff adjoint-based aerodynamic shape optimization problems. A special attention is paid to flexible inner–outer GMRES strategy combined with most relevant preconditioning and deflation techniques. The choice this specific class solvers challenging problems based on its outstanding convergence properties. Typically in our implementation efficiency preconditioner enhanced a domain decomposition method overlapping. However, maintaining performance may be since scalability technique properties often antagonistic each other. In paper we demonstrate how able overcome critical issue. numerical study performed considering either Finite Volume (FV), or high-order Discontinuous Galerkin (DG) discretization which affect arithmetic intensity memory-bandwidth algebraic operations. We consider test cases transonic turbulent flows RANS modeling over two-dimensional supercritical OAT15A airfoil three-dimensional ONERA M6 wing. Benefits terms robustness compared standard obtained. Strong analysis shows satisfactory results. Based these representative discussion recommended practices proposed.
منابع مشابه
Krylov space solvers for shifted linear systems
We investigate the application of Krylov space methods to the solution of shifted linear systems of the form (A+ σ)x− b = 0 for several values of σ simultaneously, using only as many matrix-vector operations as the solution of a single system requires. We find a suitable description of the problem, allowing us to understand known algorithms in a common framework and developing shifted methods b...
متن کاملHigh order ILU preconditioners for CFD problems
This paper tests a number of ILU-type preconditioners for solving indeenite linear systems which arise from complex applications such as Computational Fluid Dynamics. Both point and block preconditioners are considered. The paper focuses on ILU factorization which can be computed with high accuracy by allowing liberal amounts of ll-in. A number of strategies for enhancing the stability of the f...
متن کاملAdaptive sparse linear solvers for implicit CFD using Newton–Krylov algorithms
We consider the simulation of three-dimensional transonic Euler flow using pseudo-transient Newton–Krylov methods [8,9]. The main computation involves solving a large, sparse linear system at each Newton (nonlinear) iteration. We develop a technique for adaptively selecting the linear solver method to match better the numeric properties of the linear systems as they evolve during the course of ...
متن کاملa comparative study of the relationship between self-, peer-, and teacher-assessments in productive skills
تمایل به ارزیابی جایگزین و تعویض آن با آزمون سنتی مداد و کاغذ در سالهای اخیر افزایش یافته است. اکثر زبان آموزان در کلاس های زبان از نمره نهایی که استاد تعیین میکند ناراضی اند. این تحقیق جهت بررسی ارزیابی در کلاس های زبان انگلیسی به هدف رضایتمندی زبان آموزان از نمره هایشان انجام گرفته است که در آن نمرات ارائه شده توسط سه گروه ارزیاب (ارزیابی خود دانشجو، همسالان واستاد) در مهارت های تولید (تکل...
15 صفحه اولذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Computers & Fluids
سال: 2022
ISSN: ['0045-7930', '1879-0747']
DOI: https://doi.org/10.1016/j.compfluid.2022.105575