heat of combustion


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heat of combustion,

heatheat,
nonmechanical energy in transit, associated with differences in temperature between a system and its surroundings or between parts of the same system. Measures of Heat
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 released during combustioncombustion,
rapid chemical reaction of two or more substances with a characteristic liberation of heat and light; it is commonly called burning. The burning of a fuel (e.g., wood, coal, oil, or natural gas) in air is a familiar example of combustion.
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. In particular, it is the amount of heat released when a given amount (usually 1 molemole,
in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules.
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) of a combustible pure substance is burned to form incombustible products (e.g., water and carbon dioxide); this amount of heat is a characteristic of the substance. Heats of combustion are used as a basis for comparing the heating value of fuels, since the fuel that produces the greater amount of heat for a given cost is the more economic. Heats of combustion are also used in comparing the stabilities of chemical compounds. For example, if equal quantities of two isomeric hydrocarbons burn to produce equal amounts of carbon dioxide and water, the one releasing more energy (i.e., with the higher heat of combustion) is the less stable, since it was the more energetic in its compounded form.

heat of combustion

[′hēt əv kəm′bəs·chən]
(physical chemistry)
The amount of heat released in the oxidation of 1 mole of a substance at constant pressure, or constant volume. Also known as heat value; heating value.
References in periodicals archive ?
Paliwa stale--Oznaczanie ciepla spalania i obliczanie wartosci opalowej [Solid fuels Determination of the heat of combustion and calculation of net calorific value].
1) It is common to describe energy values or heat of combustion values as higher heating values (HHV) for moisture-free material and gross heating values (GHV) or lower heating values (LHV) for material containing moisture.
The average heat of combustion was not changed significantly with the addition of 8 wt% OMMT, which is typical of condensed-phase flame-retardant mechanism in polymer-layered silicate nanocomposites.
Theoretical calculation of heat of formation and heat of combustion for several flammable gases.
This empirical principle is based on the observation that, generally, the net heat of combustion of any organic material is directly related to the amount of oxygen required for combustion so that approximately 13.
The tarpaulins/geotextiles had an average heat of combustion value 2.
The material's physical form (solid, liquid, gas, powder, or sludge), viscosity, volatility, flash point, melting point, and heat of combustion affect the incineration technique.
Samples were tested at Southwest Research Institute and met or exceeded D-1655 requirements including net heat of combustion, freezing point, smoke point and sulfur levels.
Research of the resulting char was followed up by the test method described in LST EN ISO 1716:2010 Reaction to fire tests for products--Determination of the gross heat of combustion (calorific value), which is applied to determine reaction to fire classes A1 and A2 according to LST EN 13501-1:2007.
However, the recoverable heat of combustion was higher for trees that had been dead longer, as a result of lower wood MC.
To decrease the typical HRR established fire retardants usually reduce the combustion efficiency and/or effective heat of combustion of the volatile pyrolysis products (flame inhibition, fuel dilution), decrease the amount and rate of combustible volatiles (charring, barrier formation/intumescence) or cooling the system in the gas or condensed phase (water release, endothermic reactions.