A British company, Epicam, is developing a turbulence grid to help control the motion of the fuel/air mixture before it enters the engine.
The grid is mounted on the upper surface of the inlet valve, creating high-speed microturbulence in the mixture as it enters the combustion chamber. The grid's microturbulence has advantages over the eddies (turbulence) in current lean-burn engines. Large eddies can cause problems in initial ignition and later in the engine's cycle, when the ignited mixture can lose heat via a 'scrubbing' effect on the cylinder walls, or even extinguish itself.
A problem with the turbulence grid is that it can impede the airflow into the engine, which reduces the power, but with careful design this can be kept to minimum.
In an ideal, 100 per cent efficient internal combustion engine, the fuel would burn to give just ...