On a numerical method for liquid filled systems

In this paper, an unconditionally stable algorithm is proposed for the dynamic analysis of incompressible fluid filled systems. This approach decouples the fluid and structural effective stiffness matrices via a mixed finite element method. The two resulting matrices are shown to be symmetric and sparse and the semibandwidths of both matrices are small when they are compared to that of the traditional implicit method. Consequently, the potential saving in computer storage and cost is clearly significant. The comparisons of this numerical method with the traditional implicit method are also given in this paper. Results show: (1) the algorithm is accurate and unconditionally stable; (2) there are large increases in computational efficiency; and (3) the computer storage reduction factor can be higher than 12.