Modeling and vibration behavior of porous rectangular plates

A numerical and experimental study is presented to investigate modeling and vibration behavior of a thin rectangular i sotropic plate with distributed small holes. Such porous plate (namely, a plate with many small holes) may be used to reduce the total weight in weight-sensitive structures. Up to the present, the modeling technique for the problem has not been established yet due to the difficulty of incorporating effects of relatively small-sized holes in the plate vibration theory. In this report, a method is proposed to analyze vibration of such porous plates by developing a representative plate element where a circular hole is located in the center of the element. Numerical examples include sets of natural frequencies calculated for the porous plates with three different boundary conditions, and the variations of fundamental frequencies are presented with changing the number and location of holes on a square plate. The validity of such computational model is examined by comparing the numerical results with experimentally determined frequencies for aluminum porous plates.