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. The results of this development work demonstrate the potential of the AVL High Compression Lean Burn (HCLB) Combustion System with regard to fuel economy improvement and exhaust emission reduction.
Results of the development program described in this paper prove that the homogeneous charge, lean burn principle, as realized in the AVL-HCLB engines, represents a feasible solution for compact and medium-sized passenger cars complying with US and European emission standards.