Cycle to Cycle Diesel Combustion Characterisation During Engine Transient Operation

In the paper is described how to characterise the combustion process of a high speed turbocharged direct injection diesel engine (HSDI) during a transient process, which consists on a full load acceleration at constant engine speed, known as load transient. The combustion characterisation is based on the cycle to cycle combustion analysis and the Rate of Heat Release calculation (RoHR).

The information presented in the paper includes, the transient recorded data at three different engine speeds joint with information about transducers characteristics and measurement frequencies. The post-processing of the obtained information and its synchronization is described in detail; a protocol of the process is finally obtained. The RoHR of every transient cycle is calculated and shown as final objective of the work. To conclude, relevant information about mechanical efficiency, maximum in-cylinder pressure, diesel combustion phases starting and duration is also obtained from the transient process analysis by means of a combustion diagnostic code.