Monopropellant droplet burning

Burning monopropellant droplets have the spherical configuration shared by burning fuel droplets in an oxidizing atmosphere and the pre-... 

Kiley (35) attempted to burn liquid monopropellants in nitrogen by the method of suspended droplets and by the technique of a porous Alundum sphere (7 mm. in diameter). These experiments did not yield stable combustion in an inert gaseous atmosphere. For combustion in air he reports the evaporation constants for hydrazine and nitromethane (Table IV). 

The liquid rocket proplnts are introduced into the combustion chamber of a rocket through an injector in the form of droplets. The droplets then vaporize at their surface and the vapors start to burn. The mechanism of burning differs, however, depending upon whether the propint is a monopropellant or bipropellant, and, if a bipropellant, whether it is hypergolic or nonbypergolic... 

In the monopropellant system each droplet is like every other and the vapors produced are the same in ccmpositicn(consisting of a fuel and an oxidizer). When these vapors are heated to their ignition pointfby means of a special igniter), they burn without any air being introduced from outside... 

A monopropellant is a fuel that is capable of reacting exothermically without an oxidizer. Numerous such fuels are known many are liquids. A droplet of liquid monopropellant can burn in an inert atmosphere without an oxidizer. There are rockets that employ liquid monopropellants as fuels for propulsion in some applications these are better suited than bipropellant rockets that employ a liquid fuel and a liquid oxidizer. The relevance of monopropellant droplet combustion to the operation of monopropellant rockets and fundamental curiosity have prompted studies of the subject. 

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