At 06:04 2/07/98 GMT, someone wrote:
>> The problem occurs when the firing frequency and the resonant frequency
>> are the same.
Couldn't the resonant frequency also be a harmonic of the firing frequency?
A 300 Hz firing frequency in a 6-cylinder corresponds to an engine speed of
3,000 rpm. Perhaps the noted resonance could be also excited by engine
speeds of 1,500 rpm, or 750 rpm. In this case, the balancing and harmonic
damping of the crankshaft may damp out all of these resonant modes except
one. Does it, in fact, occur at only one engine speed?
Has anyone read the appropriate chapters in Design of Machinery, yet? Maybe
they could expand further?
Allen Nugent
Graduate School of Biomedical Engineering
University of New South Wales
Sydney 2052 Australia
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