The main characteristic of gasoline is the octane number

In this article, "The main characteristic of gasoline is the octane number" we will tell you about the octane number, what it is and that it defines where it is used. Almost all modern machines use 4-stroke engines. Each cycle affects the inclusion of compression when the piston begins to compress the combustion chamber a mixture of fuel and air before a spark to ignite its spark. The compression ratio engine is also called the size of the compression mixture. Gasoline engines may also have compression ratio 8-1. _ So octane fuel tells us about how it can be compressed before it spontaneously ignite. If a mixture of gasoline ignited not by a spark, but because of the compression, it will knock. It will lead to very serious damage to your engine, so it must be fought. Know that the low-octane gasoline (say, A-92 is easy to cope with a smaller aspect ratio before ignition). The desired octane number determines the compression ratio engine. Increased compression ratio - this is one of the ways how to increase engine power, without changing its volume. The main advantage of any engine with a higher octane rating - is, of course, his power. Again, its main drawback - it's too expensive fuel. Incidentally the word "octane" has the following origin: When crude oil was subjected to "cracking" on the refinery plant, then received a huge amount of hydrocarbon chains CH, their chains were of different lengths. These chains can easily be separated from each other and get different kinds of fuel. You've probably heard somewhere on methane, butane and propane. Certainly in chemistry classes. This hydrocarbons. Methane is a molecule in a single carbon atom. In turn, every molecule of propane is always in a chain of 3 carbon atoms. But Bhutan has a chain of 4 atoms, pentane - of 5, hexane - 6, heptane - of 7, but the octane - 8. For your information, with heptane handles compression disgusting. Contracting, it immediately ignited. But octane contrary to cope with it pretty good - easily applied compression, non-flammable. Petrol AI-98 is somewhere in the 92% of octane and somewhere in the 8% of heptane. The mixture ignites spontaneously only in the presence of a certain aspect ratio and is only used in engines that do not exceed this level. Even during the First World War, found that significantly increase the octane number is possible, if adding tetroetilovy lead (TEL). This allowed us to use too much cheaper grades of fuel, which added to TEL. Thus, the concept of "lead" or "ethyl" gasoline. Unfortunately, even with such a fuel has its drawbacks: for example, lead can score and make it a catalyst for a few minutes unusable. Earth would be covered with a thin layer of lead, which would make toxic all living things, including humans. At a time when lead was banned, gasoline went up immediately because many refineries are not able to constantly increase the octane number of new low-cost fuel. Today is allowed to use lead only to airlines, aircraft engines because you want to use a higher octane rating over 100. In this case, 100 is a characteristic of the fuel is not the percentage of octane in the fuel. TEL additives can increase the compression ratio of fuel, but exclude the addition of octane. At the moment, engineers have begun work on a new fuel that will be made specifically for the aircraft, it would exclude the addition of lead additives. And yet, aircraft engines run on kerosene.