A main part of the “EmIQ Combustion Process“ is the alternative combustion technology. In principle the alternative diesel combustion process used at AVL, is based on partial mixture homogenisation and low temperature combustion. Both factors are achieved by adequate charge dilution with high rates of recirculated exhaust gas and the adjustment of an optimal start of injection, with respect to combustion.
As, however, the required EGR rates are quite high and combustion velocity increases with increasing load, such combustion processes are only suitable for part load operation. For real life engine operation, a combination of alternative and standard combustion processes is therefore necessary.
The successful application of alternative combustion strategy has to be seen in close connection with the related engine control strategy. Closed loop combustion guided control strategy is seen as the prime direction for successful application of alternative combustion as well as to improve the effects of series emission scatter.
In combination with the EmIQ closed loop combustion control the alternative combustion strategies can be demonstrated in vehicle.