Pyrogen igniter

In a comparative study, it was found that MTV (SR 886B) (mass ratio 55/40/5) has a lower rocket propellant ignition delay than typical AP-based propellant formulations used in pyrogen igniters [4]. 

There are a variety of igniter designs which are currently employed in solid-propellant rockets. These types include rocket-exhaust (pyrogen), pyrotechnic, and hypergolic igniters, each of which can be located in the head-end closure of the motor or in the exhaust nozzle at the aft-end of the motor. The heat-transfer information appropriate to each of these possible combinations is discussed in the following sections. 

Pyrocore = detonating fuse for rocket ignition pyrogen 271... 

On the other hand, v/hen we ignite a mixture of some pyrogen(e.g. milk sugar potassium chlorate 3 6) and the same dye contained in a canister with a small hole, we have a good smoke with quite a pretty colour which jets out of the hole. The particles are sketched through the microscope as Fig.53.2. In this case the burning gas of the pyrogen plays the role of the B-substance and completely prevents the cohesion of the dye particles. 

Concerning the nature of the pyrogen there are three main requirements firstly the quantity of the heat generated must be large as far as possible, secondly it must be ignited at a relatively low temperature and also be able to continue burning at a relatively low temperature. Lastly it must produce as large a volume of gas as the B-substance. 

If the temperature of the pyrogen falls below its ignition temperature, it will be extinguished. 

Thus the ignition temperature for the pyrogen must be significantly less than 300 C. 

Only chlorate oxidizers produce pyrogens with sufficiently low ignition temperatures for use with organic smoke dyes. 

The processes of thermal decomposition play an important role in various practical fields including metallurgy, mineral conversion processes, pyrogenic chemical technology, pyrolysis and thermal treatment of wood and coal, com-hustion of natural and synthetical fuels, coal carbonization, the prevention of grain spontaneous ignition, and so on. There is still a need for scientifically well-founded approaches to control the thermal decomposition of materials. Many studies focus attention on the chemical transformations and reactions in the pyrolized systems and on the creation of mathematical models of such processes as the major parts of the theory of chemical decomposition of complex substances. 

Pyrogenic decomposition at low temperatures of organic salts such as tartrates. This process yields self-ignitible metal powders of small particle sizes,... 

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