Improvements to Diesel Passenger Car Refinement

981033

02/23/1998

Event
International Congress & Exposition
Authors Abstract
Content
Diesel engines have become increasingly popular as a power unit for passenger cars over the last decade, due mainly to their superior fuel economy. The first generation of high speed direct injection engines suffered from a lack of refinement by comparison with contemporary spark ignition engines. Analysis of subjective assessments of typical diesel engine noise identified impulsive sounds and the excitation of low frequency resonances as the major reasons for adverse subjective reaction.
In addition torsional resonances in the drive train can be excited by fuelling variations as a result of interactions between hydraulic waves in the fuel injection drillings and pipes (time dependent) and the pump filling and injecting events (speed dependent). Drivetrain resonances can be excited also by rough clutch engagement, road imperfections and sudden increases in fuelling in response to driver demand. These effects have been analysed in some detail and a model-based analysis technique is described which is adequate to develop fuel injection equipment. A parametric analysis identifies the key features in the mechanical components.
Combustion noise from diesel engines can be controlled at source by injection rate modulation, as described in a previous SAE paper. Recently refinement targets for diesel engine noise have been expressed as equalling the best spark ignition engine noise Research into subjective assessment of impulsive noise has indicated a method by which improvements to combustion noise may be assessed.
Meta TagsDetails
DOI
https://doi.org/10.4271/981033
Pages
15
Citation
Russell, M., and Hulot, O., "Improvements to Diesel Passenger Car Refinement," SAE Technical Paper 981033, 1998, https://doi.org/10.4271/981033.
Additional Details
Publisher
Published
Feb 23, 1998
Product Code
981033
Content Type
Technical Paper
Language
English