《MSC_experience》.pdfVIP

Part I 1. System warning message 7661 *** SYSTEM WARNING MESSAGE 7661 (ROTDR1) THE MASS ON ROTOR 1 AT GRID 103 DOES NOT PASS THE SYMMETRY TEST USER INFORMATION: RESULTS MAY BE INACCURATE Such a situation maybe ascribe to an error of define CONM2, please check it. 2. System warning message 5289 *** USER FATAL MESSAGE 5289 (WRGMTD) DEPENDENT DEGREEOFFREEDOM GRID ID =101 AND COMPONENT =2 APPEARS ON MORE THAN ONE MPC OR RIGID ELEMENT ENTRY. Such a situation maybe ascribe to an error of define RBE2, change the nodes, try it. 3. Definition of Unbalance The definition of UNBALNC: UNBALNC, 100,1.0E6,102,0.0,1.0,0.0 4. User fatal message 9050 ^^^ USER FATAL MESSAGE 9050 (SEKRRS) ^^^ RUN TERMINATED DUE TO EXCESSIVE PIVOT RATIOS IN MATRIX KLL. ^^^ USER ACTION: CONSTRAIN MECHANISMS WITH SPCI OR SUPORTI ENTRIES OR SPECIFY PARAM,BAILOUT,1 TO CONTINUE THE RUN WITH MECHANISMS. If negative terms o ur on the factor diagonal matrix during matrix decomposition using the SPARSE (default) solver, UFM 9050 will correctly be printed, but the DOF containing negative factors on the factor diagonal matrix will not be identified. Terms which have factor diagonal ratios greater than the value of PARAM,MAXRATIO will be properly identified. Avoidance: If the problem is run using NASTRAN SPARSE=1, the degrees of freedom with negative terms in the factor diagonal matrix will be properly identified in the listing. The reason maybe: (1) a rigid translation, some dofs were not constrainted (2) a rigid connection between the two elements. (3) there are some duplicated nodes in the model. The Equivalence action should be executed. 5. Grid Point Singularity Table 导致奇异性的原因，通常是表达结构的单元没有将相邻单元的对应节点的自由度连接起来。识别奇异 性自由度的原则，也针对于这个方面，用户应仔细检查分析集的奇异自由度，并清除它们。 M