A New Measuring Method for the Direct Determination of Diesel Engine Combustion Noise

Previously indirect test methods were used to investigate Diesel engine combustion noise. Now digital signal analysis gives the possibility of determining it and its narrow band spectra directly. Such a method for direct evaluation of the combustion noise is described and the possibilities offered by it are shown. A single-cylinder direct-injection Diesel serves as a test engine. Steady-state as well as transient conditions of the engine are evaluated by the procedure.