Many people may misunderstand the phenomenon of black smoke from warships, thinking that this is a manifestation of backward technology. But I didn't know it was normal.
When a warship with complete power starts normally, it often emits a small amount of black smoke. The black smoke may be related to the use of power or fuel, such as those warships equipped with diesel or oil-fired boiler power systems, because of fuel.
Specifically, one is a dynamic factor. Generally speaking, warships generally choose engines suitable for their own characteristics through diesel, steam, gas and other ways. For all-electric propulsion warships, it is also inseparable from the use of the above means for power generation.
These diesel engines and other power plants need to be propelled by heavy oil with higher cost performance. Heavy oil is a special raw material that is significantly different from light oil. The so-called heavy oil comes from the residue after normal extraction of crude oil, which is mainly composed of hydrocarbons, sulfur and other substances. From the characteristics analysis, this raw material has high viscosity, macromolecules and low purity. Because it can't burn fully, warships using heavy oil will produce black smoke.
From the above statement, the power system and fuel used by warships are important reasons for the breeding of black smoke.
Specifically, destroyers and frigates are equipped with diesel engines or diesel-fuel combined power systems in pursuit of high speed. The former has the advantage of low fuel consumption, even lower than gas turbines and boiler turbines.
Diesel engines or diesel-electric hybrid power systems are generally installed on destroyers all over the world. Of course, the disadvantages of diesel engines are also obvious, such as poor mute effect. Those warships equipped with high-power diesel engines are more concerned with cost performance. However, whether the warship uses diesel engine or not, as long as heavy oil is used, black smoke will appear in the process of starting navigation, which is inevitable.
However, it is worth noting that if destroyers and frigates use gas power, the phenomenon of black smoke will be completely gone. It's not that the military doesn't want to use heavy oil, but that the aerodynamic force can't accommodate heavy oil!
In addition, the aging of the engine body and the imperfect maintenance in the later period are also the reasons for the black smoke, because this leads to the failure of effective atomization of heavy oil and insufficient combustion.