Internal Combustion Engine - cause and effect chain

<div><i>Cause and effect chain for an internal combustion engine, exemplary for a 4 stroke gasoline engine. The overall process is divided into three consecutive phases: intake flow, spray formation/mixing and combustion. Within these phases several fundamental phenomena and physical sub-processes can be identified. The progression of each phenomena/process is highly sensitive towards its initial and boundary conditions. The interaction of all processes constitutes a complex system, in which instabilities are amplified and may evolve in time and space. For this reason, at the same crank angle of successive cycles differing (flow) conditions develop. These varying conditions are referred to as cycle-to-cycle variations (CCV).</i></div>