Combustion heats, explosives

Al tshuler, L.V., Equations of State and Structure of Compressed and Heated Bodies, presented at the Second All-Union Symposium on Combustion and Explosion, Erevan, October 25-30, 1969. 

Interaction of powdered boron and steam may become violent at red heat [1]. The highly exothermic reactions with water might become combustive or explosive processes at sufficiently high temperatures and pressures [2],... 

Energy of explosion. The energy of explosion values given in Table 16.2 should be considered as the theoretical maxima, and yield factors of 10% are considered reasonable for fuel-air explosions. For equivalent volume storage, hydrogen has the least theoretical explosive potential of the three fuels considered, albeit it has the highest heat of combustion and explosive potential on a mass basis. 

Boiling-liquid expanding-vapor explosion (BLEVE) A BLEVE occurs if a vessel that contains a liquid at a temperature above its atmospheric pressure boiling point ruptures. The subsequent BLEVE is the explosive vaporization of a large fraction of the vessel contents possibly followed by combustion or explosion of the vaporized cloud if it is combustible. This type of explosion occurs when an external fire heats the contents of a tank of volatile material. As the tank contents heat, the vapor pressure of the liquid within the tank increases and the tank s structural integrity is reduced because of the heating. If the tank ruptures, the hot liquid volatilizes explosively. 

Combustion, Heat of. Its definition is given in Vol 2 of Encycl, p C9-L, under Calorific Value and a brief description is given on ppClO Cll. More complete description is given in this Section under Detonation (and Explosion), Heats of... 

Heats of combustion of explosives deficient in oxygen (See Vol 1 of Encycl, p A515, under "Available Oxygen ) are always higher than either their heats of explosion or of detonation. For expls with positive oxygen balance to CO2, like NG, there should not be any difference between these values Values for heats of combustion may be found in the same sources as indicated under "Heat of Formation . Some selected values for explosives are given in the Table which is at the end of "Heat of Explosion and Heat of Detonation ... 

D) G.B. Kistiakowsky, "The Heats of Combustion of Explosives , OSRD 702 (July 1942) [Heats of combstn of 50 nitrated compds were detd heats of formation were calculated heats of expln deton velocities... 

E) G. Stegeman, "Heat of Combustion of Explosive Substances , OSRD 5306(July 1945) [Detn of Qcombstn of 21 expl compds 2 nonexpl compds heats of formation at const press were calcd]... 

The unified approach adopted by Ma ek assumed that all initiations are ultimately thermal. More precisely every initiating stimulus (shock, impact, electric discharge, friction, etc) serves to heat up the explosive or a portion thereof, initially at a temperature T to an elevated temperature T. It is assumed that T and the length of time t the explosive is exposed to T are the two variables sufficient to account for initiation. The 3rd factor influencing the reaction rate, density p, is important in gaseous combustions and explosions where it varies considerably with temperature and pressure in homogeneous solids and liquids it is nearly constant... 

The solution of the Poisson-Boltzmann equation with. the application to thermal explosions) 5) D.A. Frank-Kamenetskii, "Diffusion and Heat Exchange in Chemical Kinetics, pp 202-66, Princeton Uni v-Press, Princeton, NJ (1955) (Quoted from MaSek s paper) 6) L.N. Khitrin, "Fizika Goreniya i Yzryva (Physics of Combustion and Explosion), IzdMGU, Moscow (1957)... 

EXPLOSION HEATS OF FORMATION, COMBUSTION, DEFLAGRATION, EXPLOSION AND DETONATION. See Vol 4, pp D369-L to D384-R... 

CA 20,1732C1926)( Apparatus contg an electrically heated cataiyst which glows more brightly if combustible or explosive gases are present in the air) 2)H.F.G8rlacher, Chem Fabrik 1935,... 

Bomb for Determination of Heats af Combustion and Explosion. See under Calorimetric Tests... 

Muraour et al(Ref 5,p 273) define "potentiel apparent" as the heat of explosion or deflagration, as detd in a calorimetric bomb at const vol either, in vacuum or in inert atmosphere. This differs from chaieur de combustion" (heat of combustion) which is detd in the bomb in the presence or an excess of compressed oxygen. In the opinion of Muraour et al, it is much simpler, less time consuming, and more precise to aet ana use the values of heat of combustion in lieu of calorimetric values... 

By heat losses capable of stopping propagation we mean those processes which lower the combustion temperature. These include (1) heat transfer from the heated explosive mixture to the tube walls, (2) evacuation of heat from the reaction zone itself to the walls of the container and (3) evacuation of heat from the reaction zone to the combustion products which depends on the cooling of the reaction products—cooling of the products creates a drop in temperature as one moves away from the reaction zone and a corresponding longitudinal (in the direction opposite the direction of propagation) heat flux. 

Over the last 10-15 years, interest has grown significantly in the kinetics of combustion and explosion reactions, which are characterized by the presence of some mechanism of acceleration of the reaction. This acceleration, which leads to ignition, may be related either to the accumulation of active products which catalyse the reaction, the chain carriers (autocatalysis, chain explosion), or to an increase in the temperature of the mixture due to heat release in an exothermic chemical reaction (thermal explosion). 

This paper is a continuation of a series of theoretical studies carried out at the Institute of Chemical Physics which seek to give a description of various phenomena of combustion and explosion under the simplest realistic assumptions about the kinetics of the chemical reaction. A characteristic feature of the specific rate (rate constant) of chemical combustion reactions is its strong Arrhenius-like dependence on the temperature with a large value of the activation heat, related to the large thermal effect of the combustion reaction. 

Although most explosive incidents have involved mixtures of the chlorate with combustible materials, the exothermic decomposition of the chlorate to chloride and oxygen can accelerate to explosion if a sufficient quantity and powerful enough heating are involved. A case history of a fire-heated explosion of a store of 80 t of chlorate is given. The more stable sodium chlorate will also explode under similar... 

Generally speaking, combustion is a heat-releasing chemical oxidation reaction, which is often accompanied by the occurrence of a flame. Flame temperatures differ widely from approx. 2000 K for an open flame to approx. 3000 K for the flame of an acetylene cutting torch. Remarkably, the heats of combustion of explosives is generally lower than those of common fuels (pine wood with 12.9% water 4.422 kcal/g, acetylene 11.923 kcal/g, dynamite 75% 1.290 kcal/g. 

Calorimetric Tests. See Heat of Formation, Combustion, Deflagration, Explosion and Detonation... 

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