Showing papers on "Ammonium perchlorate published in 1986"

Investigation of high pressure solid propellant combustion chemistryusing emission spectroscopy

Abstract: A survey of the chemiluminescent emission in the range from 280 and 800 nm from the flames of ammonium perchlorate (AP)and HMX-based solid propellants has been performed at pressures from atmospheric to 7 MPa (1000 psig). The AP propellant flame showed the emission of CH, CN, NH, and OH at atmospheric pressure (under nitrogen), as well as emission from several trace impurities such as Na, K, and Ca. As the pressure was increased, the banded molecular emission of all molecules except OH was rapidly obscured by a continuum that spanned the range 350-550 nm. In contrast, the HMX propellant showed CN, NH, and OH emission at pressures up to 7 MPa. CH emission was not detected in the HMX flame at any pressure; C2 emission was not detected in either propellant flame. Spatial intensity distributions of emitting species were obtained, showing OH and atomic emission spatially distributed throughout the propellant flame and CN and NH emission confined to the region near the surface.

Combustion wave structures of ammonium perchlorate composite propellants

Abstract: The combustion wave structures of ammonium perchlorate composite propellants have been studied experimentally by means of thermal analysis and microthermocouple techniques. Two types of binders are used in order to examine the impact of binders on the burning rate characteristics. The binders used are hydroxy terminated polybutadiene (HTPB) and hydroxy terminated polyester (HTPE). The oxygen concentration of the HTPE is much higher than that of the HTPB. The results of thermal analysis show that HTPB decomposes exothermically and HTPE decomposes endothermically. The reaction time in the gas phase just above the burning surface is calculated based on the data obtained by the temperature distribution measurements in the combustion waves. The reaction rate of HTPE propellant is found to be higher than that of the HTPB propellant. Though the heat feedback from the gas phase to the burning surface of the HTPB propellant is smaller than that of HTPE propellant, the burning rate of HTPB propellant appears to be higher than that of HTPE propellant. The results obtained show that the chemical properties of binders play an important role not only in the reaction rate in the gas phase but also in the heat release at the burning surface.

Low Pressure Burning of Ammonium Perchlorate Composite Propellants

Abstract: The combustion wave structure of ammonium perchlorate (AP) composite propellants was observed by microphotographs and the heat transfer process from the gas phase to the con-densed phase was determined by microthermocouples. Since the thickness of the combustion wave increased with decreasing pressure, the experiments were conducted at low pressures below I atm in order to examine the structure as detailed as possible. It has been determined that the reaction zone in the gas phase consists of heterogeneous flamelets produced by the decomposed AP monopropellant flames and the decomposed gases of polymeric fuel binder. The thickness of the reaction zone decreases with decreasing the concentration of binder at a constant pressure. The heat feedback from the gas phase to the condensed phase and the heat release at the burning surface are very dependent on the type of binder used. The reaction rate in the gas phase is greater and the heat release at the burning surface is smaller for the binder (HTPE)...

Gel type slurry explosive and matrix and method for making same

Abstract: A matrix material to be added to a standard ammonium nitrate-fuel oil dry explosive to form an economical slurry explosive having excellent water resistant properties includes an oxidizer solution chosen from the group of an aqueous sodium perchlorate solution, an aqueous ammonium perchlorate solution, an aqueous calcium nitrate solution, or a combination thereof, along with a fuel such as ethylene glycol or fuel oil and a thickening agent such as a guar gum in combination with an acid such as glacial acetic acid. The oxidizer solution generally makes up about 94%-97% by weight of the matrix. The slurry explosive is made by mixing the matrix with a standard ammonium nitrate-fuel oil dry explosive and then adding a cross linker to the mixture so that it forms a gel. The matrix may make up between about 14% to 40% by weight of the explosive, and preferably makes up about 20% by weight.

The bonding ability and bonding site of a new ferrocene based silicon compound in composite solid propellants

Abstract: Ammonium perchlorate (AP: 70-85 wt%) and carboxy or hydroxy terminated polybutadiene (CTPB or HTPB: 15-20 wt%) constitute the major ingredients of commonly-used composite solid propellant systems. The polymer, in addition to its function as a fuel, acts as a binder for the structural integrity of the solid propellant.

Kinetics of complexation of ammonium perchlorate, silver(I) perchlorate, and thallium(I) perchlorate with the macrocycle 18C6 in dimethylformamide

Abstract: Cinetique etudiee de 5 a 40°C. On trouve des effets attribuables a la polarisabilite du cation et a la directivite de la liaison. Parametres thermodynamiques

Process and apparatus for the production of solid propellants

Abstract: 1. Process for the production of solid propellants, e.g. composite ram jet propellants, comprising at least one pulverulent oxidizer, e.g. ammonium perchlorate, a prepolymer binder as the fuel, optionally further solid fuels and additives, such as plasticizers, stabilizers, burn-off moderators, in which the aforementioned components are mixed and shaped to propelling compositions, accompanied by the addition of a hardener, characterized in that for processing non-pourable mixtures with a viscosity of >= 1000 Pa.s, the components are mixed in kneader in vacuo, the hardener is added to the mixture accompanied by further mixing and the finished mixer is extruded directly from the kneader into a propellant form in opposition to a counterpressure.

Burning Rate Studies of Energetic Double Base Propellants

Abstract: A systematic study was carried out on the combustion characteristics of CMDB propellants containing ammonium nitrate, ammonium perchlorate, potassium nitrate, potassium perchlorate, RDX and PETN. While ammonium and potassium perchlorates increased burning rates, other additives maintained either the same burning rate or reduced burning rates marginally. Propellants containing these additives showed marginally higher peak temperatures, indicating interaction among the species of double base propellant decomposition and those of additives.

Particle Radiative Feedback in Ammonium Perchlorate Deflagration

Abstract: The deflagration behavior of ammonium perchlorate (AP) with carbon black and copper chromite catalyst additives was studied over a pressure range of 4.3-171 MPa (50-2500 psig) using light transmission and emission measurements in a window bomb and burn rate measurements in a conventional strand burner. It was found that a maximum value of the lower pressure limit PDL exists at intermediate values of carbon black concentration similar to that already reported for copper chromite catalyst. It was also found that sufficiently high concentrations of carbon black augment the steady deflagration rate of AP. Since carbon black is not a catalyst of AP decomposition , it is postulated that particle radiative feedback is more likely to be the cause of the observed behavior than previously suggested catalyst effects. To quantify the amount of radiative heat feedback, flame temperature and emissivity values were calculated from light emission/transmission measurements. These calculations yielded flame temperatures between 1406 and 1449 K and a value for the effective particle absorption efficiency over diameter Qa/d of 4.1 jun"1 in good agreement with expected values. A simple analysis shows that the observed trends (increasing PDL at low particle concentrations and decreasing PDL at higher concentrations) can be predicted from simple radiative transfer considerations together with particle and matrix continuity equations.

Changes in the Calorimetric Value and Ignition Temperature of Composite Solid Propellants During Ageing-A Note

Abstract: Calorimetric value and ignition temperature of carboxy terminated polybutadiene/ammonium perchlorate propellant decrease during accelerated ageing. The behaviour has been explained on account of binder loss and condensed phase reactions in the propellant matrix.

Mechanism of Catalysed & Inhibited Decomposition of Ammonium Perchlorate

Abstract: between IX, the fraction decomposed, and time I. The equation is known to satisfy thermal decomposition of AP for a wide range of temperatures in the presence and absence of catalysts and inhibitors. The model shows that constant (a) is associated with nucleation process and (h) is associated with adsorption of HCI04• This is conflfUled by adsorption experiments which show that there is significant adsorption of HCIO4 on catalysts for which h value is large while the adsorption is negligible for inhibitors for which h::l::: O. Greater adsorption of HCI04 in the case of catalysts and negligible adsorption in case of inhibitors is also suggested by pH studies of partially decomposed samples of AP. The model is found to support the data on thermal decomposition of metal perchlorates.