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Development of the concept vehicle Magna Innovative Lightweight Auto (MILA) by using simulation tools is described in this paper. The vehicle combines a high degree of flexibility for design and sportiness with the ecologically relevant fuel Natural Gas (NG). The figures with regard to increased cruising range and reduced costs are derived from the concept vehicle. An innovative technology for NG storage systems points out new ways for the future, automotive NG storage technology in a vehicle. The paper refers to the interrelation of weight/costs and the increased fuel efficiency of a NG powered vehicle.

This paper deals with development and optimization of combustion process, cold start system and exhaust after-treatment carried out on the steady state and transient test bed as well as with vehicle development on chassis dynamometer and on the road at standard ambient temperatures and under cold conditions of a) SPFI or MPFI-SI engine with catalyst (closed loop), neat ethanol fuelled, compared to b) glow plug assisted direct injection methanol engine equipped with oxidation catalyst. The main emphasis is laid on the optimization of the cold start behaviour with and w/o catalyst in order to obtain low emissions, primarily during the first phase of the FTP 75 cycle. The emission results show that with both engine types the achievement of US-1994 limits will be possible, including a very low aldehyde emission.

During the last four years FIAT AUTO has cooperated with AVL in the development of three generations of ethanol vehicles for the Brasilian market for current, 1992 and 1997 Brasilian emission standards. This paper deals with suitability of ethanol as SI-engine fuel combustion system development and calibration strategies for 1992 lean burn engines and 1997 TWC-concepts transient and warm up development single fuel cold start systems TWC emission control requirements vehicle performance, fuel economy, emissions with and w/o catalyst. The paper shows that the concepts chosen allow calibrations with sufficient margin with respect to emission standards. Cold start and driveability can be developed for single fuel operation down to 0 deg. C. Vehicle driveability and performance are on a competitive level. For aldehyde control the TWC is a very good solution. Application problems with TWC can occur if the catalyst is located remote from the engine.

Research and development activities on high-performance S.I. engines for passenger car application are mainly concentrated on full load performance development as well as the development of combustion systems and engine structures in order to meet future market and legislation requirements. This paper presents results out of AVL's R&D work in the field of multi-valve S.I. engines. Variable Intake Systems of different design are compared to Variable Valve Timing devices with respect to overall engine performance. Engine and vehicle test results of a four-valve engine with the AVL developed C̱ontrolled Ḇurn Ṟate (CBR) combustion system are presented and analyzed. The control of charge stratification, charge motion and hence of the combustion pattern turns out as a major requirement for the investigated advanced combustion systems.

AVL's research work on advanced combustion systems for four-stroke gasoline engines has revealed a strong influence of charge motion and mixture preparation on engine performance, especially exhaust emissions and fuel economy. This paper presents the effects of mixture preparation and charge motion revealed in studies of AVL High Compression Fast Burn (HCFB) combustion systems. Major combustion parameters were investigated and optimized. Control of charge stratification emerged as one of the key elements of advanced combustion systems for both two-valve and four-valve engine configurations. Consequently, measures for charge stratification control are also presented.

The AVL-HCLB ( High Compression Lean Burn) Combustion System development work, carried out on a single cylinder research engine and a first generation 4IL engines for passenger car application, has led to intensified R&D acitivity on soma particular features of the AVL System to enable its full fuel economy potential to be realized -while still conforming with current and proposed exhaust emission standards. It is shown that, compared with cast iron, aluminum is the better cylinder head material also for HCLB engines. A Variable Swirl Intake Port developed at AVL has enabled WOT ( Wide Open Throttle) performance and upper part load NOx emissions characteristics to be improved. By means of an air flow/fuel flow and engine speed governed engine management system, the upper part load BSFC and NOX emission trade off of the HCLB-englnes has been optimized. An EGR-valve with a non linear flow characteristic has proven to be an important contributing factor in this respect.

The market-driven need to further improve the fuel economy of passenger cars, while meeting current and anticipated future emission regulations, represents a challenging target for today's engine research and engineering. Based on the results of intensive spark ignited engine combustion system research work. AVL has developed a development strategy that is responsive to both the require-rents of expected limitations in worldwide energy supply and to current and proposed exhaust emission standards. This strategy is presented in this paper. Supported by single cylinder research engine investigations into the combustion phenomena of lean homogeneous mixtures, multi-cylinder engine development has been carried out on two in-line (IL) four cylinder engines, of 1.6 and 2.3 litre displacement, respectively.