Search Results

The conception of new engines as well as the further development of those already existing, is influenced to an ever accelerating extent by the aspects of cost, besides the need for driveability, fuel economy and ecological conservation. For an independent engine manufacturer it is especially important to be able to offer products that, considering the competition in terms of performance, fuel consumption, exhaust emissions and noise levels, have favourable price ranges. The growing need for environmental preservation, in particular, has forced the introduction of normaly more expensive technology such as new injection and turbocharging systems. In relation to the criteria involved in minimising the production costs, this results in a conflict of objectives.

As a response to the more and more stringent noise emission legislation and increasing requirements of acoustic driving comfort, a new high speed DI Diesel engine family has been designed focusing on noise control at source, minimization of secondary noise control measures and improvement of sound quality. The present paper reviews optimization work during design stage with respect to combustion and structure behavior, as well as during test bench development work on noise emission reduction. Results of the main development steps are illustrated referring to engine design features. structure optimization and application of secondary noise reduction measures. Focusing on sound quality, the engine noise was analyzed with appropriate psychoacoustic software and improvement due to different modifications is illustrated.