Influence of Operating Cycle on Noise of Diesel Engines

The fundamental effect that cycle difference of a reciprocating internal combustion engine has on noise and performance, together with noise and vibration characteristics of 2- and 4-cycle diesel engines, is described.

Some of the conclusions drawn from extensive noise and vibration measurements include:

1. 1.
   Variation in engine surface vibration and noise radiated is linearly related to a force input applied to the structure.
2. 2.
   A method of predicting combustion noise levels of current automotive diesel engines.
3. 3.
   A combination of engine performance calculations with relations for predicting overall engine noise in initial design stages.