ソルバー
Solving Models with Step Changes to Loads in Time
ソリューション番号: 1245 バージョン: All versionsHow should I model loads that change magnitude at a particular time? I am solving a transient model which has loads that change instantaneously in time, but the solver appears to be missing some of these changes in ...
Manually Setting the Scaling of Variables
ソリューション番号: 1240 バージョン: All versionsThe default behavior of the software is to assume a different scaling for each set of variables in your model. These scale factors are by default automatically determined, but sometimes may need to be manually tuned. ...
Manually setup the geometric multigrid solver
ソリューション番号: 1213 バージョン: All versionsThe geometric multigrid solver accelerates the convergence of the iterative solver by solving the finite element problem on a series of meshes rather than a single one. The multigrid algorithm starts with the initial ...
Solving time dependent models with inconsistent initial values
ソリューション番号: 1172 バージョン: All versionsA common mistake when setting up transient models is to have initial conditions that are inconsistent with the loads and boundary conditions. This occurs most often when running transient fluid flow studies, but the ...
Improving Convergence of Nonlinear Stationary Models
ソリューション番号: 103 バージョン: All versionsStationary (time-invariant) models with nonlinearities may converge very slowly. A nonlinearity can be introduced into the model either in the governing equation, or by making any of the material properties, loads, or ...
Improving convergence in nonlinear time dependent models
ソリューション番号: 1127 バージョン: All versionsWhen I look at the Solver Log of a time dependent model, I see that the NLFail column has non-zero entries: Step TimeStepsize Res JacSolOrderTfailNLfailLinErrLinRes 0 0-out 23208e-14 3.5e-15 ...
Structural Contact Modeling Guidelines
ソリューション番号: 1102 対応: MEMS Module, Structural Mechanics Module バージョン: All versionsThis article contains guidance for solving models that include structural contact, and the procedures that should be followed to achieve a converged solution. Background Structural contact modeling is a highly non ...
COMSOL and Multithreading
ソリューション番号: 1096 バージョン: All versionsThis solution describes how COMSOL takes advantage of multicore computers. COMSOL supports two mutual modes of parallel operation: shared-memory parallelism and distributed-memory parallelism (cluster support). Shared ...
BDF, Generalized Alpha, and Runge-Kutta Methods
ソリューション番号: 1062 バージョン: All versionsWhat numerical methods are available when using a Time-Dependent Solver? What are their relative benefits and when should I use them? The Time-Dependent Solver offers three different time stepping methods: The ...
Error: "Out of memory"
ソリューション番号: 1030 バージョン: All versionsI get an error message, that contains the words Out of memory, for example: Out of memory during LU factorization. or Out of memory during assembly # Background Before resolving this issue, you should go through ...