Car exhaust hazards has been a concern for everyone, in fact, diesel engines compared to gasoline engines thermal efficiency of 30%, with more power, longer life, better power performance, so it is widely used in large vehicles engine, but due to the vehicle's own problems as well as oil quality issues and other factors, many diesel vehicles exhaust emissions are not up to standard, which will aggravate the air pollution situation, then, diesel What are the methods of control of automobile exhaust?

 

Diesel fuel in the combustion will produce a large number of carbon particles and nitrogen oxides N0X, in order to eliminate them, both the environmental protection department or automobile manufacturers have a variety of ways.

Currently the United States for the use of diesel vehicles in the provision of the addition of DPF. DPF (Diesel Particulate Filter) - Diesel Particulate Filter, installed in the diesel vehicle exhaust system, through the filtration to reduce the particulate matter in the exhaust (PM) of the device. This device that filters 99% of particulate matter seems to be more effective at the moment. This is the improvement work done in the exhaust system. However, if the problem is to be solved at the source, it is still necessary to start from the design of the engine. The advent of electronically controlled diesel injection systems is a big step forward in improving energy consumption and reducing emissions. Better control of diesel fuel timing and dosing injection into the cylinder, as well as better atomization, can fundamentally make the diesel fuel more fully combustion reaction, improve power and reduce emissions at the same time. For example, the pre-injection process is set up before the main injection, i.e., a small amount of diesel fuel is injected, which can shorten the ignition delay period of the main injection and greatly reduce the emission of nitrogen oxides. Electronically controlled common rail, electronically controlled pump nozzles and electronically controlled monobloc pumps and other technologies allow diesel vehicle emissions to reach "National III" or "Euro III" standards.

There is another system in cars that you may not have heard of, but it has been around for many years, and it is called EGR (Exhaust Gas Recirculation) - Exhaust Gas Recirculation System. It is an exhaust gas cleaning device for NOx, one of the harmful gases in engine exhaust. By sending part of the exhaust gas from the engine to the intake manifold and re-entering the cylinder with the fresh mixture, a large amount of carbon dioxide lowers the combustion temperature of the mixture and reduces the amount of NOx generated.