AUTOMOTIVE EXHAUST PIPE: THE MODAL ANALYSIS APPROACH FOR DESIGN AND TESTING

摘要

The application of the modal analysis to the vibrational study of an automotive exhaust pipe is illustrated. The knowledge of the vibrational response of the pipe is fundamental for the fatigue life prediction and for duration tests. After having review the state of art of the exhaust pipe test procedure, the pipe configuration and the vibration sources to which the pipe is submitted, the experimental modal analysis is applied to obtain the resonances and the mode shapes of an European salon car exhaust pipe. The test procedure is discussed, pointing out the necessity of the use of a three axis accelerometer and of a four channels signal analyzer to get a convenient picture of the motion of the pipe. At least, the advantages obtained using the modal analysis technique are enhanced, both for design and testing.