The JCG solver also starts with element matrix formulation.Instead of factoring the global matrix,the JCG solver assembles the full global stiffness matrix and calculates the DOF solution by iterating to convergence (starting with an initial guess solution for all DOFs).The JCG solver uses the diagonal of the stiffness matrix as a preconditioner.The JCG solver is typically used for thermal analyses and is best suited for 3-D scalar field analyses that involve large,sparse matrices.
For some cases,the tolerance default value (set via the EQSLV,JCG command) of 1.0E-8 may be too restrictive,and may increase running time needlessly.The value 1.0E-5 may be acceptable in many situations.
The JCG solver is available only for static analyses,full harmonic analyses,or full transient analyses.(You specify these analysis types using the commands ANTYPE,STATIC,HROPT,FULL,or TRNOPT,FULL respectively.) You cannot use this solver for coupled-field applications (SOLID5 or PLANE13).
With all iterative solvers,be particularly careful to check that the model is appropriately constrained.No minimum pivot is calculated and the solver will continue to iterate if any rigid body motion is possible.
這個是軟件幫助說明解釋這種算法,要弄明白,還得看其他的對比方法,看
Basic Guide | Chapter 3.Solution |
3.2.Types of Solvers
部分對算法的說明