Does Touareg ea839 engine have stratified combustion?

The Touareg ea839 engine uses stratified combustion. The advantages of stratified combustion are high thermal efficiency, small throttling loss, and limited fuel can be converted into working energy as much as possible. In stratified combustion mode, the throttle valve is not fully opened to ensure a certain degree of vacuum in the intake pipe to control exhaust gas recirculation and carbon canister. At this time, the torque of the engine depends on the fuel injection quantity, and has little to do with the intake air quantity and the ignition advance angle.

Matters needing attention in stratified combustion

In stratified combustion mode, the throttle opening is relatively large during the intake process, which reduces a part of throttle loss. The key in the intake process is to install a replica in the intake manifold, which replicates the principle of upward opening. The actual model may be different to seal the lower intake manifold, so that the intake air can accelerate through and cooperate with the top of the V-shaped piston to form a phase intake vortex.

The mixture is formed in the range of crank angle of 40-50 degrees Celsius. If it is less than this range, the mixture cannot be ignited; If it is greater than this range, it will become homogeneous. The air-fuel ratio of stratified combustion is generally between 1.6-3. When igniting, only the gas with good mixing state around the spark plug is ignited. At this time, the surrounding fresh air and the gas of exhaust gas recirculation form good thermal insulation protection, which reduces the heat dissipation of the cylinder arm and improves the thermal efficiency.