Remote Combustion Sensing Methodology for Non-Intrusive Cylinder Pressure Estimation in Diesel Engines

The pollutant emission reduction requested by future pollutant emission policies spawned a great deal of research in the field of combustion monitoring and closed-loop control. This is especially true for Diesel engine, since an important reduction in NOx and particular matter will be required. Many works demonstrate that a major engine-out emission reduction can be achieved through a closed-loop combustion control methodology based on cylinder pressure trace processing. However, the main obstacles to the use of cylinder pressure sensors for on-board application are measurement reliability over time and cost. Therefore, this paper describes the development of a methodology that allows estimating cylinder pressure through a proper combination of the information coming from low-cost sensors mounted on the engine.