The mechanism of Diesel cetane number improver
As the current Diesel fuel cetane asks is ceaseless rise, Diesel cetane number improver’s price also will be more and more high, and now the world is more and more strict with the Diesel exhaust, so it is necessary to develop both economical and environmentally friendly new type of cetane number improver, and the Diesel cetane number improver, the mechanism of this work is very necessary.
In diesel engine combustion process is short and complicated physical and chemical process, can make a continuous combustion process is divided into four different stages, namely, ignition delay period, rapid combustion period, slow-burning period and complementary combustion period.
In diesel engine, air is first high temperature and high pressure cylinder compression, when diesel to mist sprayed into the combustion chamber, not burning, immediately the first heating, evaporation, diffusion and mixing with air to form a combustible mixture, such as a series of physical process before burning. Only when the temperature increased to a small part of the diesel combustion temperature after burning. Starting diesel spray into the cylinder to the fire started this a period called the ignition delay period, only 1 ~ 3 ms. Ignition delay period is short, but it has a decisive influence on the engine work. The longer the ignition delay period, accumulated in cylinder of diesel fuel, the more once in rapid combustion period will lead to a dramatic increase in pressure and temperature in the cylinder, causing the engine work rough, appear even knocking phenomenon. The higher diesel cetane number, the shorter ignition delay period, therefore, improve the fuel cetane number is helpful to shorten the ignition delay period of combustion.
Diesel cetane number improver added effect withDiesel cetane number improver is decomposed to generate the structure, the number of free radicals. Therefore, cetane number improver of carbon chains and the kinds of substituent will affect the degree of increase cetane number.