Stabilized Solution to Spurious Mode Problem and Ill-Conditioning in Interface Force Based Substructure Coupling Method

Table 2

The mode frequency comparison using different matrix Gs; orders were kept.

Order	Exact	Gs=Is	Gs=Ms	Gs=Ks	Gs=Rs
1	0.0000	0.0000	0.0000	0.0000	0.0000
2	6.5712	6.5713	6.5713	6.5714	6.5712
3	7.0001	7.0022	7.0022	7.0226	7.0001
4	7.6090	7.6131	7.6131	7.6103	7.6090
5	12.8444	12.8487	12.8487	12.8537	12.8445
6	18.7891	18.7935	18.7935	18.8111	18.7894
7	27.0282	27.1237	27.1237	27.2344	27.0636
8	32.0634	32.0658	32.0658	32.1554	32.0652
9	33.1482	33.7795	33.7795	33.5493	33.6621
10	35.4645
Averaged Relative error (%)		0.30095	0.30095	0.348863	0.211159