Reduction of Exhaust Emissions and Fuel Consumption by Premixed Type Diesel Combustion (Third Report)

‐Robustness Improvement by Model Based Control for Ignition Timing and Multi -stage Injections‐

Abstract

A PCI (Premixed Compression Ignition) combustion concept which achieves simultaneously low emissions and fuel consumption has applied to a new developed engine whose compression ratio is extremely low value 14.0. The robustness improvement of the fuel consumption, emissions, and noise in transient condition, which was one of the issues of PCI combustion for practical use, has achieved by means of the following techniques: -Model based ignition timing control, in which the ignition delay was predicted by Arrhenius type extended empirical formula with the model constants by DOE, and Livengood-Wu integration. -Restriction of spray mixture homogeneity by multi-stage injection.