in Shang Diesel Power Generation Units Under normal operating temperatures, the emitted fumes should be colorless or light gray. The so-called colorless, not a little color, not as colorless as a gasoline engine, but light gray, colorless, this is a normal exhaust smoke. The exhaust smoke of a diesel engine may be heavier at idle and may be heavier at high speeds and high loads. In order to judge and analyze the abnormal smoke exhaust of the Shangchai diesel generator set, it is necessary to observe the normal smoke exhaust. After the fuel of Shangchai diesel generator set burns, the normal color is generally light gray, and when it is slightly heavy, it is dark gray. In the work of diesel engines, smoking often occurs. There are four types of smoke exhaust: black smoke, blue smoke, white smoke and gray smoke. This is one of the conditions for judging the failure of the Shangchai diesel generator set. The specific analysis is as follows:

       Black smoke (soot) in the exhaust of Shangchai diesel generator set

       Black The smoke is also crazy. The main cause of black smoke in the exhaust of Shangchai diesel generator set is that the fuel mixture concentration is too high, the combustible mixture is poorly formed or incompletely burned. Under high temperature and high pressure combustion conditions, some carbon-based small particle solids formed by partial anoxic, pyrolysis and dehydrogenation are the manifestations of incomplete combustion of fuel in the combustion chamber. Due to the uneven combustion of the diesel engine, the chemical reaction conditions in different regions of the combustion chamber are different and change with time, and black smoke may be generated in various ways. Diesel is a complex hydrocarbon. The unburned diesel fuel injected into the combustion chamber is pyrolyzed to form carbon black, which forms black smoke when discharged together with the exhaust gas. Black smoke is a product of incomplete combustion and is a product of the release and aggregation of hydrocarbons during combustion cracking under high temperature and anoxic conditions. In some cases, the fuel injection of the Shangchai diesel generator set will form a liquid oil film on the combustion chamber wall, which is part of the evaporation. Its combustion depends on the evaporation rate and mixing rate of the fuel vapor and oxygen. If the oxygen concentration in the surrounding gas is too low or the mixing speed is insufficient, the fuel gas evaporated by the oil film will be decomposed, resulting in unburned hydrocarbons, incomplete oxidation products, and black smoke.