EGR Chemistry Abbreviation

Entropy Gradient Reversal

Exhaust Gas Recirculation

Exhaust gas recirculation is a nitrogen oxide (NOx) emissions reduction technique used in petrol/gasoline and diesel engines. EGR works by recirculating a portion of an engine's exhaust gasback to the engine cylinders. Exhaust gas is routed back into the combustion chamber because the exhausted air is much hotter than the intake air. EGR works by diluting the N2 and providing gases inert to combustion (CO2 primarily) to act as an absorbent of combustion heat to reduce peak in cylinder temperatures. NOx is produced in a narrow band of high cylinder temperatures and pressures.