Exhaust Gas Recirculation (EGR)

The power system of diesel engines is equipped with an exhaust gas recirculation system (EGR), allowing to reduce the amount of harmful nitrogen oxides emitted into the atmosphere (NO _x). To do this, part of the exhaust gases is again fed into the combustion chambers of the engine, which makes it possible to lower the combustion temperature and thereby reduce the content of harmful substances in the exhaust gases. The recirculation process is controlled by the control unit of the DDE system, which, based on the signals from the accelerator pedal position sensors, crankshaft speed, atmospheric pressure, coolant temperature, issues commands to change the cyclic fuel supply. In accordance with this, the control unit, using a vacuum control valve, applies vacuum pulses to the EGR valve and ensures the correct dosing of the amount of recirculated exhaust gases. The EGR valve is located at the intake manifold. At low coolant temperatures and when high engine power is required, exhaust gas recirculation does not take place. The EGR system does not require maintenance.