NVH-MEasurements - Noise, Vibration, Harshness
The radiation of structure-borne sound in the audible and perceptible range is the focus of attention in the development of drive trains and rotating machines of all kinds. It is particularly important to comply with comfort functions and regulations on sound emissions. The cause of structure-borne noise is excitation by rotating machines. These cause the enclosures and touching machine parts to vibrate due to a non-uniform rotary motion. Finally, the correlation between cause and effect is taken into consideration to investigate the totality.
For this purpose, the speed of the vibrating machine, which in this case is an internal combustion engine, is measured. In the following, the effects can be measured by means of accelerometers and microphones and then evaluated together in the order and frequency range. ROTEC offers high-resolution analogue measuring cards with ICP inputs and special NVH features in the analysis software for NVH investigations.
The recorded measured values are evaluated in the time and spectral domain. The acoustic behavior is also analyzed.
Keywords: structure-borne sound, rotating machines, sound emissions
- Analysis of the characteristics of structure-borne sound signals over time or shaft revolutions
- Correlation between dynamic movement of components and noise effects
- Causal research of gear rattling or similar NVH issues
- Visualization of the composition of a soundscape
- Analysis of single orders and total noise level
- Analysis of the conspicuousness and dominance of a noise component
- Detection of resonances
- Comparison of the sound image at different locations
- Verification of the effectiveness of sound insulation