Application of Wavelet Analysis to Determine the Start of Combustion of Diesel Engines

The operation of Diesel engines now days has demanded higher thermal efficiency and lower emission to achieve low cost operation and to comply emission regulation. It is well known that the start of combustion will decide the quality of combustion. The start of combustion can be used to analyze the injection process and also the combustion process. In this work, wavelet analysis is used to determine the start of combustion will be discussed in this paper. The common method to determine the start of combustion is normally using the second order derivation of combustion chamber pressure. This method is used to validate the results from wavelet analysis. The experiments are conducted using several types of Diesel engines operated in several operating conditions. The results show consistently coincidence between start of combustion determined from pressure transducer and determined from the wavelet analysis in any rpm and load.