Rockets as the type of weapons, there are a very long time.The pioneers in this business were Chinese, as mentioned in the hymn of the Middle Kingdom beginning of XIX century."The red glare of rockets" - just like it is sung.Charges of gunpowder invented, as we know, in the same China.But, to "red light" shone, and the heads of the enemies attacked the fiery arrows were needed rocket engines, even the simplest.Everyone knows that the gunpowder explodes, and for the flight must be directed to the intense burning gas emission.So that the composition of the fuel had to be replaced.When ordinary explosive ingredients ratio is 75% nitrate and 15% carbon and 10% sulfur, the rocket engines contain 72% nitrate, 24% carbon, and 4% of sulfur.
In modern solid-fuel missiles and accelerators are used as fuel mixture more complex, but the principle remains the same, the ancient Chinese.Its advantages are indisputable.This simplicity, reliability, high speed initiation, relative cheapness and ease of use.To round started, it is enough to ignite the solid fuel mixture, provide a flow - and he flew.
However, there is a proven and reliable technology of its shortcomings.First, initiating combustion of the fuel, it can not be stopped, as well as change the combustion mode.Second, oxygen is required, and in conditions of underpressure or vacuum not.Third, burning still proceeds too quickly.Out
were looking for many years, scientists in many countries, finally found.Dr. Robert Goddard in 1926 tested the first liquid rocket engine.As it is used gasoline fuel mixed with the liquid oxygen.For the system to work stably for at least two and a half seconds, Goddard had to solve a number of technical problems associated with the pump injection reagent cooling system and the steering mechanism.
principle on which all built liquid rocket engines, is extremely simple.Inside the case are two tanks.From one of them through the mixing head of the oxidant is supplied to the expansion chamber, where the presence of a catalyst in the fuel supplied from the second tank, goes into a gaseous state.There is a combustion reaction, hot gas passes first converging subsonic nozzle area and then expanding supersonic, which is also supplied fuel.The reality is much more complex, requires a cooling nozzle, and modes of supply - a high degree of stability.Modern rocket engines as a fuel can be supplied with hydrogen, oxidant is oxygen.This mixture is highly explosive and the slightest abnormality of any system leads to an accident or disaster.The components of the fuel can also be other substances that are not less dangerous:
- kerosene and liquid oxygen - they were used in the first stage of the program carrier "Saturn V" in the "Apollo";
- alcohol and liquid oxygen - have been involved in the German V2 rockets and Soviet media "East";
- nitrogen tetroxide - monomethyl - hydrazine - used in engines "Cassini".
Despite the complexity of the design, liquid rocket engines are the primary means of delivery of cargo space.They are used in intercontinental ballistic missiles.Modes of operation be precisely regulated, modern technology allows to automate processes in their units and units.However
rocket engines for solid fuels and have not lost their value.They are used in space technology as a subsidiary.Veliko their value in the braking modules and salvation.
