The paper describes the setup of a 4-cylinder 1.4-liter prototype Spark Ignited (SI)-engine, which is highly boosted, extremely downsized and port fuel injected. During experimental data gathering with the engine it was discovered that the originally mounted fuel injectors were non-optimized an unable to produce an expected low fuel consumption performance at low speed, low load engine working conditions.
To solve this problem by finding an optimized alternative solution for the mixture preparation process it was decided to use a high-performance numerical simulation tool. The paper presents the overall layout of the prototype engine as well as the structure of the 3-D dynamic optimization tool used to address the mixture preparation problem.
The paper continues with a detailed description of the different steps used to reach the complete optimization of the mixture preparation system (both the fuel injectors and the intake manifold).
The paper concludes by a presentation of a series of experimental verification data obtained on the prototype engine both at the engine test rig as well as preliminary data from measurements carried out with the engine mounted in a passenger car.