求教模态计算的几个设置

zhgjun

virtual.lab做natran模态的前处理的两个问题请教一下。
要求只输出部分节点的模态信息，我把这些节点做了一个group，在vector output request里引用这个组，如图1所示，这样是否正确？
图2这个标签里的设置都是什么，是否用于设置残余向量的设置？各选项分别在什么情况下适用。

lengxuef

关于Nastran的参数可以看一下Nastran的手册。
自己看一下这个：
MECHFIX
Default = AUTO
Control for fixing the massless mechanism problem.  The new capability is provided automatically for
the default of this parameter, listed above.  The new capability is executed only when the eigensolution
does not provide answers because of symptoms consistent with the presence of massless mechanisms.  If
MECHFIX is set to YES, the constraint modes are removed before attempting an eigensolution.  When
set to NO, the new capability is blocked, and the eigensolution uses the pre MSC.Nastran 2001 rules, i.e.,
three failed shifts and a fatal exit.