EGRsüsteemi

EGRsüsteemi, an abbreviation for Exhaust Gas Recirculation system, is an emissions control technology used in internal combustion engines. Its primary function is to reduce the formation of nitrogen oxides (NOx), which are harmful pollutants contributing to smog and acid rain. The system works by recirculating a small portion of exhaust gases back into the engine's intake manifold.

When exhaust gases are mixed with the fresh air-fuel mixture entering the combustion chamber, they act as an inert gas. This dilutes the oxygen content and lowers the combustion temperature. High combustion temperatures are a key factor in the formation of NOx. By reducing these temperatures, the EGR system effectively inhibits the chemical reactions that produce NOx.

The EGR system typically consists of an EGR valve, which controls the flow of exhaust gas, and associated passages. The valve's operation is usually managed by the engine control unit (ECU), which determines when and how much exhaust gas to recirculate based on various engine operating conditions such as engine load, speed, and temperature. Modern EGR systems can be mechanical or electronic. Electronic EGR systems offer more precise control, leading to improved emissions performance and potentially better fuel efficiency. However, the recirculated exhaust gases contain soot and other particulate matter, which can lead to carbon buildup in the intake system and EGR valve over time, potentially requiring maintenance.