Vibroacoustic analysis of engines

Vibroacoustic analysis of engines

We perform measurements of engine noise and vibrations and the engine dyno. We have performed several dozen such measurements at various locations on the engine: both on the block, sub-systems, turbine and exhaust. We always measure the engine speed at the same time, which is necessary, for example, for Order analysis.
 
 
We have assessed the test cells for compliance with the ISO 3746 standard for the determination of sound power by the pressure method. The cells intended for acoustic tests have been adapted accordingly and the K2 correction is sufficiently low.
 
 
If this is not enough, we can also precisely determine the acoustic power of the engine at constant speeds using an intensity probe.
 
 
Measurement results can be elaborated in the form of various graphs, but we can also provide raw data as .uff, .txt, .wav files, and in other formats.

Transducers

  • Single- and three-axis vibration sensors (ICP, charge)
  • Non-contact displacement sensors (CAPACITEC)
  • IVS-500 Industrial Vibration Sensor (POLYTEC)
  • laser for measurement of torsional vibrations (Bruel&Kjaer)
  • force transducers (PCB), modal hammer (Bruel&Kjaer)
  • polarised (200V) class 1 microphone (Bruel&Kjaer and G.R.A.S.)
  • sound intensity meter (G.R.A.S.)

Analyses

  • Frequency (FFT, CPB, FRF and others)
  • Time Domain
  • Order
  • Torsional vibration measurements
  • Operational Deflection Shapes
  • Overall
  • Plots as a function of time, rotational speed, frequency, order, etc.
  • Export as: .uff, .txt, .wav, .sdf and other formats
  • We can also perform customer signal analysis (.unv, .uff, etc.)

Norms

  • SAE J1074
  • ISO 3746
  • PN-EN ISO 9614-1:2010
  • PN-EN ISO 9614-2:2000
  • PN-EN ISO 9614-3:2010

Measurement apparatus

  • We make use of multichannel DAQ devices by firms such as: Brüel&Kjaer, OROS and DEWESOFT.
Document No. Title/Description
PN-EN ISO 9614-1:2010 Acoustics - Determination of sound power levels of noise sources using sound intensity - Part 1: Measurement at discrete points
PN-EN ISO 9614-2:2000 Acoustics - Determination of sound power levels of noise sources using sound intensity - Part 2: Measurement by scanning
PN-EN ISO 9614-3:2010 Acoustics - Determination of sound power levels of noise sources using sound intensity - Part 3: Precision method for measurements by scanning
PN-EN ISO 3746:2011 Acoustics - Determination of sound power levels and sound energy levels of noise sources using sound pressure - Survey method using an enveloping measurement surface over a reflecting plane
SAE J1074 Engine Sound Level Measurement Procedure