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toaster89
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A proportionally damped 2-DOF system has mass and stiffness matrix M and K. We also know that the system has damping ratio ζ1 = 0.1 and 2 = 0.3. The damping matrix is written as
C = α M + β K + γ KM-1K
Try to find the coefficients
Mx"+Cx'+kx=0
CM^-1K=KM^-1C
Mx"(t)+(αM+βK+γKM^-1K)x'(t)+kx(t)=0
x(t)=M-.5 x q and multiply by M-.5
q"(t) + (αI+βK+γM-.5 M-.5 KM-1K)q'(t)+Kq(t)=0
q"(t)+(αI+βK+γ2M-.5K)q't+Kq(t)=0
So far this is all i got and now i am stuck
any tips?
C = α M + β K + γ KM-1K
Try to find the coefficients
Mx"+Cx'+kx=0
CM^-1K=KM^-1C
Mx"(t)+(αM+βK+γKM^-1K)x'(t)+kx(t)=0
x(t)=M-.5 x q and multiply by M-.5
q"(t) + (αI+βK+γM-.5 M-.5 KM-1K)q'(t)+Kq(t)=0
q"(t)+(αI+βK+γ2M-.5K)q't+Kq(t)=0
So far this is all i got and now i am stuck
any tips?