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This paper describes the findings of a design, simulation and test study into how to reduce particulate number (Pn) emissions in order to meet EU6c legislative limits. The objective of the study was to evaluate the Pn potential of a modern 6-cylinder engine with respect to hardware and calibration when fitted to a full size SUV. Having understood this capability, to redesign the combustion system and optimise the calibration in order to meet an engineering target value of 3×1011 Pn #/km using the NEDC drive cycle. The design and simulation tasks were conducted by JLR with support from AVL. The calibration and all of the vehicle testing was conducted by AVL, in Graz. Extensive design and CFD work was conducted to refine the inlet port, piston crown and injector spray pattern in order to reduce surface wetting and improve air to fuel mixing homogeneity. The design and CFD steps are detailed along with the results compared to target.

In catalyst heating operation for DISI (Direct Injection Spark Ignition) engines, split injection has been generally known to improve combustion stability which is critical for the trade-off between tailpipe emissions and vehicle idle NVH. This is also the case for a spray guided DISI engine employing multi-hole injectors and with both injector and spark plug centrally located in the chamber. There are some special challenges with regard to combustion robustness because of the close proximity between injector and spark plug. Investigations have been carried out through engine testing and CFD simulation to ensure combustion robustness. For catalyst heating operation, the first injection occurs during induction, which forms a relatively well mixed but lean mixture in the cylinder before ignition, and the second injection occurs close to ignition, which produces a stratified fuel rich mixture in the central region of the combustion chamber.

Suspension models are highly multivariate and require a nonlinear system to model the movements and interaction of the parameters within the suspension system. Multiple metrics must be considered to determine an optimal result. This paper describes a system for the use of a Genetic Algorithm for the optimization of automotive suspension geometries, a description of the suspension model, and the scoring mechanism. The results of this model evaluate the impact of multiple independent metrics. A combined objective function score is determined with the assistance of a user selectable weighting of metrics. The optimization algorithm is also compared to a discrete grid search.

A part-task simulator has been developed which concentrates on the functions related to transmission gear shifting in heavy duty trucks. By avoiding the complexity of full-feature simulators, a simple and cost-effective tool has been produced which allows training of the driver and study of the powertrain in a controlled environment. The components and operation of this new simulator are described, along with present and potential applications.

The classical calculation of inviscid drag, based on far-field flow properties, is re-examined with particular attention to the nonlinear effects of wake roll-up. Based on a detailed look at nonlinear, inviscid flow theory, the paper concludes that many of the classical, linear results are more general than might have been expected. Departures from the linear theory are identified and design implications are discussed. Results include the following: Wake deformation has little effect on the induced drag of a single element wing, but introduces first order corrections to the induced drag of a multi-element lifting system. Far-field Trefftz-plane analysis may be used to estimate the induced drag of lifting systems, even when wake roll-up is considered, but numerical difficulties arise. The implications of several other approximations made in lifting line theory are evaluated by comparison with more refined analyses.