Circular piston (38890)
Axi-symmetric infinite element model for circular piston
Free Field Technologies, 16, place de l'Université, 1348 Louvain-la-Neuve, Belgium
This example is a model of the form
with M, C, and K non-symmetric matrices and M singular. This is thus a differential algebraic equation. It is shown that it has index . The input of the system is f, the output is the state vector x. The motivation for using model reduction for this type of problems is the reduction of the computation time of a simulation.
This is an example from an acoustic radiation problem discussed in . Consider a circular piston subtending a polar angle on a submerged massless and rigid sphere of radius . The piston vibrates harmonically with a uniform radial acceleration. The surrounding acoustic domain is unbounded and is characterized by its density and sound speed .
We denote by and the prescribed pressure and normal acceleration respectively. In order to have a steady state solution verifying
the transient boundary condition is chosen as:
The matrices K, C, M and the right-hand side f are computed by MSC.Actran . The dimension of the second-order system is N=2025.
Download matrices in the Matrix Market format (File 1) (1983617 bytes).
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