Spark Plug Pressure Transducers for Measuring Indicated Work 780148
Spark plug pressure transducers were used in an experimental study to determine the suitability of such devices for measuring indicated work in internal combustion engines. Three piezoelectric transducers were studied to compare response of the spark plug unit with a reference device; the comparative data were obtained from a single-cylinder engine fitted with both a flush mounted pressure transducer and a spark plug pressure transducer. Signals from both transducers were recorded simultaneously, combined with a volume function, and analyzed for output differences. The volume function used in the calculations of indicated work was generated about an angular reference point recorded with the pressure data. Typically, indicated work calculated from the spark plug pressure transducer was found to be from -3.2 to +7.6% of that calculated from the flush mounted pressure transducer. The sources of inaccuracy associated with the spark plug pressure transducer are discussed.