Burn rate (chemistry)

About: Burn rate (chemistry) is a research topic. Over the lifetime, 847 publications have been published within this topic receiving 8908 citations. The topic is also known as: Burning rate.

Solid propellant rocket motor

Abstract: A solid propellant rocket motor having a controlled rate of thrust buildup to a desired thrust level by the combined utilization of a regressive-burning controlled flow solid propellant igniter and a progressive-burning main solid propellant charge wherein the igniter is capable of operating in a vacuum and sustaining the burning of the propellant below its normal L* combustion limit until the burning propellant surface and motor chamber pressure has increased sufficiently to provide a stable motor chamber pressure.

Solid propellant burn rate, propellant gas flow rate, and propellant gas pressure pulse generation control system and method

Abstract: Systems and methods of controlling solid propellant burn rate, propellant gas pressure, propellant gas pressure pulse shape, and propellant gas flow rate, rely on pulse width modulation of a control valve duty cycle. A control valve that is movable between a closed position and a full-open position is disposed downstream of, and in fluid communication with, a solid propellant gas generator. The solid propellant in the solid propellant gas generator is ignited, to thereby generate propellant gas. The control valve is moved between the closed position and the full-open position at an operating frequency and with a valve duty cycle. The valve duty cycle is the ratio of a time the control valve is in the full-open position to a time it takes the valve to complete one movement cycle at the operating frequency. The valve duty cycle is controlled to attain a desired solid propellant burn rate, propellant gas pressure, propellant gas pressure pulse shape, and/or propellant gas flow rate.

Two-zone model for combustion of a composite solid propellant with a coolant

Abstract: A mathematical model for combustion of a propellant with a coolant taking into account the two-zone structure of the combustion front due to condensed- and gas-phase reactions was developed and examined. Formulas for the burning rate, reaction-zone temperature, and burning-rate sensitivity to internal and external parameters of the system were derived in analytical form. The burning rate was examined numerically as a function of pressure, the characteristic size of the system, component content, and thermodynamic and kinetic parameters. Recommendations are given on methods of obtaining particular ballistic properties by varying the initial parameters of the system.

Demilitarization of high burn rate propellants containing ferrocene or its derivatives

Abstract: An effective method to recover the catalyst material, ferrocene or its deatives, from high burn rate propellants comprises the method which uses compressed gas in the form of a near critical liquid to extract, remove, and recover the specific catalyst material directly from rocket motors or from chunks of cut propellant. The method comprises introducing compressed carbon dioxide into a pressure vessel containing the propellant from which the catalyst material is to be recovered. The carbon dioxide as a near critical liquid (NCL) is circulated within the pressure vessel where extraction of ferrocene or its derivatives directly from the propellant takes place. The NCL with extractibles is transported to a warming and recovery zone where the extractibles are recovered after the carbon dioxide is volatilized and returned for recycling, compressing, and further extracting after being adjusted to a near critical liquid. Analytical data indicates that from 99.8% to 100% of ferrocence or its derivatives is readily recoverable from propellant which is undergoing demilitarization after it is determined to have burning rate, sensitivity, or other measureable changes to be out of system specification. After recovery of the high dollar value catalyst material, the propellant can be safely handled for removal using conventional water jet apparatus to cut and remove the propellant for reclamation of any of the propellant ingredients.