OS-V: 0386 Vibrating Sphere

Test No. CA1Modal Frequency Response Analysis test.

Figure 1.

Model Files

Before you begin, copy the file(s) used in this problem to your working directory.

Benchmark Model

The model is a sphere with 1m Radius. The frequency spectrum of the sound pressure level is generated by the pulsating sphere at 15 m from its center. The considered frequency range is from 4 to 500 Hz.

First order CQUAD4 elements are used for Sphere. Due to symmetry, only one-eighth of the sphere needs to be discretized by 48 elements. The Sphere is subjected to normal velocity of Vn = 0.1 m/s on all the surface in the radial direction. The surface of the Sphere is fixed.

The material properties are:
Density of fluid (air)
1.225 kg/m3
Speed of sound
340 m/s

Modal Frequency Analysis Results

Figure 2.