All Rockets are believed to have originated with the Chinese - perhaps before the 13th century, which is when they began to appear in the European country. However it's was not until the 20th century that rockets propulsion began to be studied seriously and since in the second world war rockets are the become a big weapon. The space exploration with the satellite propelled by rockets engines began in 1957 with the Russian satellite sputnik l.
Today all weather and communications satellite are regularly put in to orbit about the earth using rocket engines with cryogenic engines.
One of the some factors determine which fuel and oxidizer to use is mass of the fuel and oxidizer required. The natural gas such as gasoline have higher fuel values per gram than does coal. This difference is causing by the higher hydrogen content of natural gas and gasoline. The Hydrogen element of lowest density and the same time it is react exothermically with oxygen to give water. Hydrogen and oxygen to be combined an ideal fuel - oxidizer combination. The thermochemical reaction for the combustion of hydrogen is, of kerosene a
H₂ (ɡ)+ 1/2 O₂ (ɡ)→ H₂O (ɡ); ∆H⁰ =-242 kj
It's value of ∆H⁰ is equivalent to 120kj/g of the fuel (H₂) compared with 50 kj/g of methane. The second and third stages of saturn V launch vehicle that sent a three man Apollo crew to the moon used H₂/O₂ system. The launch vehicle contained liquid hydrogen ( boiling point at - 253⁰C) and liquid oxygen, or LOX (boiling point - 183⁰ C)
The first stage of liftoff used kerosene and oxygen gas, and unbelievable 550 metric tons ( 550× 10³) of kerosene were burns in 2.5 minutes. It's a interesting to calculate the average rate of energy production in this 2.5 minute interval. Kerosene is approximately C₁₂H₂₆, the thermo chemical equation is,
C₁₂H₂₆(l) + 37/2 O₂→ 12CO₂(ɡ) + 13H₂O(ɡ) ;
∆H⁰= - 7513 kj
This value of ∆H⁰ is equivalent to 44.1 kj/g. Thus 550× 10⁶ɡ of these fuel generating 2.43× 10¹⁰ kj in 150 (2.5 min) Each second the average energy produced was 1.62×10¹¹ watts, or 217 million horsepower there's 1 horsepower equals 745.7 watts or j/s)
The landing module for the apollo mission used a fuel made of hydrazine, N₂H₄, and derivative of hydrazine. The oxidizer was dinitrogen tetroxide, N₂O₄. These compound substances are normally liquids and are therefore easier to store than liquid hydrogen and oxygen. This reaction of the oxidizer with hydrazine is,
2N₂H₄(l) + N₂O₄(l) → 3N₂ (ɡ)+ 4H₂O(ɡ);
∆H⁰= - 1049 kj
The solid propellant are also used as rocket fuels. The mixture used in the booster rockets of the space shuttles is a fuel containing of aluminium metal powder. Oxidizer of ammoniam perchlorate, NH₄CIO₄ is mixed with the fuel.
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