SPC = 2
LOAD = 4
DISPLACEMENT(SORT1,REAL)=ALL
SPCFORCES(SORT1,REAL)=ALL
SUBCASE 4
SUBTITLE=load_case_2
SPC = 2
METHOD = 1
VECTOR(SORT1,REAL)=ALL
SPCFORCES(SORT1,REAL)=ALL
$ Direct Text Input for this Subcase
STATSUB=3
BEGIN BULK
$ Direct Text Input for Bulk Data
PARAM POST 0
PARAM PRTMAXIM YES
EIGRL 1 1 0
2. 对应于METHOD,设置相应的模态特征值提取方法:
SOL 105
CEND
TITLE = MSC.Nastran job created on 03-Jun-13 at 10:06:40
ECHO = NONE
SUBCASE 1
SUBTITLE=load_case_1
SPC = 2
LOAD = 2
DISPLACEMENT(SORT1,REAL)=ALL
SPCFORCES(SORT1,REAL)=ALL
SUBCASE 2
SUBTITLE=load_case_1
SPC = 2
METHOD = 1
VECTOR(SORT1,REAL)=ALL
SPCFORCES(SORT1,REAL)=ALL
$ Direct Text Input for this Subcase
STATSUB=1
SUBCASE 3
SUBTITLE=load_case_2
SPC = 2
LOAD = 4
DISPLACEMENT(SORT1,REAL)=ALL
SPCFORCES(SORT1,REAL)=ALL
SUBCASE 4
SUBTITLE=load_case_2
SPC = 2
METHOD = 2
VECTOR(SORT1,REAL)=ALL
SPCFORCES(SORT1,REAL)=ALL
$ Direct Text Input for this Subcase
STATSUB=3
BEGIN BULK
$ Direct Text Input for Bulk Data
PARAM POST 0
PARAM PRTMAXIM YES
EIGRL 1 1 0
EIGRL 2 1 0
修改完成后进行计算。
第二种方法:直接在Patran中进行相关设置,直接生成Nastran的bdf文件计算
同第一种方法中的第一步和第二步,然后在Analysis选项下的 Direct Text Input中选择Bulk Data Section 输入对应METHOD的模态特征值提取方法(EIGRL 卡片),然后直接进行分析计算。