To limit pollutants from transport and to reach a low level of exhaust emission, Low Temperature Combustion (LTC) modes such as Homogeneous Charge Compression Ignition (HCCI) are being studied. HCCI process is based on the auto-ignition of a highly diluted air/fuel mixture. It allows very low level of NOx and particulate emissions. But several problems must be solved: firstly the limited combustion range, the difficulty to control the combustion process, the noise but also the high HC and CO emissions. Two ways appear as very promising to improve HCCI combustion: engine technology and fuel formulation.
In this work, attention is paid on initiation and HCCI combustion control through fuel formulation. This article shows the effect of acetal addition (and in particular butylal addition) in a Diesel base fuel.
It seems to be difficult to have only an “HCCI engine” because the operation zone of the engine is too small. More likely, it will be a Diesel/HCCI engine. The advantage of acetal is to reduce significantly particulate emissions of a Diesel engine. This is an advantage for a Diesel/HCCI engine, when the engine works in Diesel combustion but it is necessary to get a better understanding of the influence of acetal addition in a Diesel base fuel during the HCCI combustion.
Butylal can have a good potential to improve the HCCI combustion by delaying the initiation of a Diesel base fuel but due to its versatile aspect, it is difficult to control, for all the experimental conditions, its effect on the initiation and the HCCI combustion of a Diesel base fuel.