Measuring Combustion Pressure Indicating System Kistler Type 5147A, 1547A, 1549A, 6617A, 6623A, 6651B measures combustion pressure in each cylinder during vehicle tests becomes important for reducing the emissions during transient engine operation.

Misfiring can be quantified and the quality of engine calibration (mapping) can be tested under real conditions. E.g., knocking combustion is detected during fast acceleration.

Racing engine electronics can be calibrated with this system in an efficient way and Kistler sensors are already used for permanent engine control on the race tracks.

The cylinder pressure signal can be displayed on an oscilloscope or transient recorder. Knocking combustion is typically detected as a superimposed oscillation of 5 to 10 kHz frequency. This oscillation is often heavier at the combustion chamber border (squish are) than in its center. The knock intensity can be quantified, e.g. with a band pass filter and an integrator. In order to avoid knocking combustion the ignition timing has to be retarded.

If the signal is recorded on crack angle base with an ADC, then parameters like IMEP, pmax or apmax can be calculated. This allows the use of algorithms for an optimal power output control of the engine.

Kistler Types 5147A, 1547A, 1549A, 6617A, 6623A, 6651B Indicating System