Identification and Quantification of Knock in Internal Combustion Engines using Spectral Analysis
Alex Gil Sanches, Felipe Soto, A. M. dos Santos, José Antônio da Silva · SAE technical papers on CD-ROM/SAE technical paper series · 2001
This work deals with knock intensity determination. It is quantified by a band-pass filter applied to the combustion chamber pressure signal, using the Fourier Transform. The filtered signal power spectrum is then calculated, as well as its integral through the ⅓ Simpson Rule, which is a measurement of knock intensity. Hence, one can analyze the influence of knock in the engine power, comparing theoretical pressure, torque and power curves with experimental ones for different knock levels.