Solving following second order matrix differential equation

1.4k Views Asked by At

Which methods (analytical or numerical) do you suggest to solve the following matrix diff. equation? And why? (Presumably analytical method)

$$ \textbf{M}\ddot{V}+\textbf{C}\dot{V}+\textbf{K}V=\textbf{P},$$ where matrices $\ddot{V}$, $\dot{V}$ and $V$ with respect to $t$ are as follows: $$ \mathbf{M} \begin{bmatrix} \ddot{V}(1,t) \\ \ddot{V}(2,t) \\ \vdots \\ \ddot{V}(n,t) \end{bmatrix} +\mathbf{C} \begin{bmatrix} \dot{V}(1,t) \\ \dot{V}(2,t) \\ \vdots \\ \dot{V}(n,t) \end{bmatrix} +\mathbf{K} \begin{bmatrix} V(1,t) \\ V(2,t) \\ \vdots \\ V(n,t) \end{bmatrix} = \mathbf{P}.$$

In here, the matrices $\textbf{M}$, $\textbf{C}$, $\textbf{K}$ and $\textbf{P}$ are as follows ($\textbf{M}$, $\textbf{C}$ and $\textbf{K}$ are $n \times n$ matrices, and $\textbf{V}$, $\textbf{P}$, $\textbf{F}$ are $n \times 1$ matrices) enter image description here

$$\mathbf{P} = \frac{P}{\rho A} \begin{bmatrix} \sin\left(\dfrac{\pi vt}{l}\right) \\ \sin\left(\dfrac{2\pi vt}{l}\right) \\ \vdots \\ \sin\left(\dfrac{n\pi vt}{l}\right) \end{bmatrix} +\mathbf{F}(t), \quad\text{where } \mathbf{F}(t) = \begin{bmatrix} f_1(t) \\ f_2(t) \\ \vdots \\ f_n(t) \end{bmatrix}.$$

In here, $l$, $P$, $A$, $\rho$, $\alpha$, $v$, $N$, $E$ and $I$ are constants. It doesn't matter what are these constants or initial or boundary conditions for me. You can select appropriate values. The matrix $\textbf{F}(t)$ is ungiven. So solution $\textbf{V}$ will depend on $\textbf{F}$.