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R. Zajac et al.
1 Introduction
The vibration sensing is a current trend in every industry. Primarily, the modal properties and the acceleration amplitudes at structurally critical places are examined
on the vibrating structure. However, the issues of vibration and noise are mutually connected, the sound power levels and sound pressure levels of the oscillating
structure are often evaluated at the final stage [1].
In this paper, a comprehensive vibroacoustic diagnosis is briefly described. This
is from the perspective of using computer simulations as well as compiling technical
measurements.
2 Technical Measurement
As outlined above, a technical experiment was applied on the simple rectangular
plate made of gray cast iron. The vibration testing was divided into two main parts:
modal and harmonic analysis.
Individual measurements were preceded by validation of main dimensions,
weighting, and pre-preparation of the structure, calibration of the used sensors
(acceleration sensors, microphones, etc.).
2.1 Geometrical and Mechanical Characteristics
of the Rectangular Plate
The basic dimensions of the plate were further considered in the calculation models:
the geometry dimensions were measured very precisely to increase the accuracy of
numerical simulation, length approx. a = 200 mm; width b = 160 mm and thickness
t = 9 mm. The density of the plate was determined from the real weight of the shell.
As mentioned above, the material of the rectangular plate was gray cast iron.
These material properties were taken into consideration in the computational model:
density ρ = 6880 kg m
−3 , Young’s modulus E = 169 GPa and Poisson’s ratio ν =
0285.
2.2 Modal Analysis Measurement Process
Free support was applied as the constraint boundary condition—structure was placed
on the low—rigidity foam.
Pulse excitation by a modal hammer was performed—applying a shock pulse at
marked points on the structure (see Fig. 1). The response scanning was mediated
R. Zajac et al.
1 Introduction
The vibration sensing is a current trend in every industry. Primarily, the modal properties and the acceleration amplitudes at structurally critical places are examined
on the vibrating structure. However, the issues of vibration and noise are mutually connected, the sound power levels and sound pressure levels of the oscillating
structure are often evaluated at the final stage [1].
In this paper, a comprehensive vibroacoustic diagnosis is briefly described. This
is from the perspective of using computer simulations as well as compiling technical
measurements.
2 Technical Measurement
As outlined above, a technical experiment was applied on the simple rectangular
plate made of gray cast iron. The vibration testing was divided into two main parts:
modal and harmonic analysis.
Individual measurements were preceded by validation of main dimensions,
weighting, and pre-preparation of the structure, calibration of the used sensors
(acceleration sensors, microphones, etc.).
2.1 Geometrical and Mechanical Characteristics
of the Rectangular Plate
The basic dimensions of the plate were further considered in the calculation models:
the geometry dimensions were measured very precisely to increase the accuracy of
numerical simulation, length approx. a = 200 mm; width b = 160 mm and thickness
t = 9 mm. The density of the plate was determined from the real weight of the shell.
As mentioned above, the material of the rectangular plate was gray cast iron.
These material properties were taken into consideration in the computational model:
density ρ = 6880 kg m
−3 , Young’s modulus E = 169 GPa and Poisson’s ratio ν =
0285.
2.2 Modal Analysis Measurement Process
Free support was applied as the constraint boundary condition—structure was placed
on the low—rigidity foam.
Pulse excitation by a modal hammer was performed—applying a shock pulse at
marked points on the structure (see Fig. 1). The response scanning was mediated