ORDER ANALYSIS OF NVH DATA ACQUIRED USING CHASSIS DYNAMOMETER
About
A vehicle in a working condition generates sounds and vibrations from different components. These noises and vibrations were recorded using different accelerometers and microphones setup on different areas of the vehicle such as the front of the cylinder head, front of the alternator, driver front outboard seat track, and driver right ear position.
Test Setup
The vehicle was run on a chassis dynamometer at part-open throttle and wide-open throttle conditions at second and third gears.
Results
Data were recorded and analyzed using Siemens Testlab to plot different color maps, order maps, and 1/3rd octave plots.
The difference between unweighted and A-weighted microphones were analyzed. Adding to this, various order maps and color maps acquired from cylinder head accelerometer, seat track accelerometer, interior mic and alternator were analyzed for resonant frequencies and source of different orders.