Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations KootK on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

penalty Method & Buckling &Dynamic solution

Status
Not open for further replies.

yusf

Structural
May 9, 2006
58
hi i have a simple question about usage of penalty method.

according to the constraints we are building P matrix and reconstructing stiffness matrix with following structure

Code:
K_new=K+C'*P*C
and simply putting it into equation KU=F and then find displacments.

that is ok but how about
during calculations for buckling and dynamic problems
do we use same approach
formulation for buckling
Code:
det(K+vK_g)= 0   eigenvalue problem
and for dynamic solutions
Code:
det(K-Mw^2)=0 eigenvalue problem
 where M mass matrix
my quesiton is that do we reconstruct K_g stifening term and M mass matrix such as

for buckling
Code:
det(K+vK_g)  K=K+C'*P*C and K_g=K_g+C'P*C
and for dynamic case
Code:
det(K-Mw^2)   K=K+C'*P*C  and M=M+C'*P*C
C is constraint matrix....

am i wrong ..if yes for buckling and dynamic case what would be the solution way..
thanks in advance
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor