Princeton Scientific Enterprises, Inc.

Exxon Research and Engineering Company

David W Blair

John P Longwell

William Bartok

Adel F Sarofim

A system and method is provided for igniting a propellant with an electrically conductive chemically insensitive polymer. The polymer is an electrical resistance heater to heat the propellant to its ignition temperature. Preferably, the polymer is an organic polymer. Surfaces of the propellant can be coated with the polymer. In the alternative, the polymer can be applied to a hollow bore in the propellant to form a self-pressurizing charge. Advantageously, the present invention controls ignition and prevents unintended ignition of the propellant.

Conductive polymer ignitors

A tubular radiant furnace having multiple radiation shields is capable of producing very high working temperatures in an extremely clean environment. A cool-walled quartz muffle tube surrounded by high temperature electrical heaters in a high temperature cavity defines the work chamber. Concentric radiation shields around the tube and the heaters are supplemented by end shields at both ends to form the high temperature cavity. The shields reduce the radiative loss from the tube and create a uniform high temperature cavity without adding significant thermal inertia to the system. The low thermal inertia leads to a fast response time for the furnace to heat up or cool down. A workpiece located within the working chamber sees the radiant field with a view factor that approaches 100 percent (100%), and this helps make possible the attainment of very high and uniform temperatures. The effect is enhanced by the proximity of the workpiece to the center of the working chamber. The furnace is capable of producing temperatures above 1,800K, and it is believed capable of operating in ranges up to 3,300K. Furnaces of this type are useful in the production of semiconductors and other materials that require very clean and uniform high temperature conditions. They are also useful in the production of materials that require very rapid heat up or cool down conditions.

Efficient high temperature radiant furnace

Fuels containing fixed-nitrogen chemical species are combusted in a multi-stage process. The process which converts substantially all of the fixed-nitrogen into molecular nitrogen (and thus avoids the formation of significant amounts of nitrogen oxides from the fixed-nitrogen) consists of four steps: (a) mixing said fuel with at least one first oxidizing agent in amounts such that the equivalence ratio of said fuel to said oxidizing agent is at least about 1.4; (b) partially combusting the mixture resulting from step (a) in at least one first stage at a first temperature of about 1850.degree. to about 2150.degree. K., with a residence time of at least 0.03 second; (c) mixing the combustion products resulting from step (b) with at least one second oxidizing agent in an amount such that the equivalence ratio of combustion products to the total amount of oxidizing agents in the mixture will be about 1.0 or less, such mixing taking place under conditions such that the temperature of the mixture will not exceed about 1800.degree. K.; and (d) completely combusting the mixture resulting from step (c) in at least one second stage at a second temperature of less than about 1800.degree. K.

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Princeton, NJ, United States of America

David W Blair