Influence of Intake Tumble Ratio on General Combustion Performance, Flame Speed and Propagation at a Formula One Type High-Speed Research Engine

General combustion and flame front propagation was investigated in a high-speed engine using ionization sensors and cylinder pressure indication. The ionization sensor system was developed to guarantee accurate and reliable flame front arrival signals. A specifically developed two-zone combustion model was used for heat release and flame speed calculations.

The two different intake tumble ratios showed large impact in some major parameters of combustion. In one case, the flame front moved towards the cooler intake valves. The low tumble engine configuration provided higher engine output and a more symmetrical flame front propagation.