Engine Vibration of a Compressed Natural Gas Engine as an effect of Combustion

摘要

In the medium to heavy duty truck market there is an increased interest to convert diesel engines currently in use to operate on compressed natural gas (CNG). For CNG to be a viable fuel for this application, it must also provide similar or improved performance characteristics compared to diesel. One such parameter is the noise and vibration output of the engine. This study investigated the relationship between the combustion pressure of a CNG engine and vibration at the engine mount locations. Multiple analysis methods for quantifying the vibration and combustion pressure were investigated to determine which provided the best data correlation. Although similar correlation trends were found with all of the analysis methods, the overall displacement provided a linear relationship with the average maximum pressure of combustion for conditions where the vibration resulting from combustion exceeded the inherent mechanical vibration. Recommendations for improvements to the test methodology are also provided.