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Accelerometer measurements of tire carcass vibrations and implications to tire-pavement noise. Tyler Dare Purdue University Robert Bernhard University of Notre Dame. Tire-pavement noise modeling. Predicted. Measured. SPL. freq. SPL. freq. Pavement parameters. Predicted. Measured.
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Accelerometer measurements of tire carcass vibrations and implications to tire-pavement noise Tyler Dare Purdue University Robert Bernhard University of Notre Dame
Predicted Measured SPL freq SPL freq
Pavement parameters Predicted Measured Tire parameters SPL Vehicle conditions freq SPL Atmospheric conditions freq
Noise prediction Noise measurement Vibration model
Propagation effects Sound absorption Noise prediction Noise measurement Vibration model Background noise Air pumping noise
Propagation effects Sound absorption Noise prediction Vibration measurement Noise measurement Vibration model Background noise Air pumping noise
Advantages Disadvantages Laser Doppler vibrometry Non-contact No field measurements Single spatial point No data from contact patch
a Embedded accelerometer t
Advantages Disadvantages Embedded accelerometer Data in contact patch Mass-loading effect Field surfaces can be measured Modification of tire Results difficult to interpret
Advantages Disadvantages Embedded accelerometer Data in contact patch Mass-loading effect Field surfaces can be measured Modification of tire Results difficult to interpret
0.2 grams Disadvantages Embedded accelerometer Mass-loading effect Mass-loading effect a Modification of tire Modification of tire t Results difficult to interpret
acceleration t wheel trigger t
acceleration t wheel trigger t
acceleration t wheel trigger t pavement trigger t
Trailing edge Exit of contact patch Entrance of contact patch Leading edge
Wheel-slap noise Contraction joints
What causes the noise? Wheel-slap noise
Speed coefficients Speed coefficient Lnoise = nLs Sound power Vehicle speed n = 0 Resonance n = 2–3 Tread block vibrations n = 4–5 Air pumping