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Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While activation energy must be supplied to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough ...
Damage to buildings, equipment and people can result from a large-scale, short-duration deflagration. The potential damage is primarily a function of the total amount of fuel burned in the event (total energy available), the maximum reaction velocity that is achieved, and the manner in which the expansion of the combustion gases is contained.
Reactions can be exothermic, where ΔH is negative and energy is released. Typical examples of exothermic reactions are combustion, precipitation and crystallization, in which ordered solids are formed from disordered gaseous or liquid phases.
Combustion is a chemical reaction that feeds a fire more heat and allows it to continue. Once a fire has started, the resulting exothermic chain reaction sustains the fire and allows it to continue until or unless at least one of the elements of the fire is blocked: foam can be used to deny the fire the oxygen it needs
GPSA currently uses 60 °F), minus the enthalpy of the stoichiometric oxygen (O 2) at the reference temperature, minus the heat of vaporization of the vapor content of the combustion products. The definition in which the combustion products are all returned to the reference temperature is more easily calculated from the higher heating value ...
A large compost pile can spontaneously combust if improperly managed. Spontaneous combustion or spontaneous ignition is a type of combustion which occurs by self-heating (increase in temperature due to exothermic internal reactions), followed by thermal runaway (self heating which rapidly accelerates to high temperatures) and finally, autoignition. [1]
The combustion may take place in a controlled manner such as in an internal combustion engine or industrial furnace, or may result in an explosion (e.g., a dust explosion). The air–fuel ratio determines whether a mixture is combustible at all, how much energy is being released, and how much unwanted pollutants are produced in the reaction.
The flame speed is the measured rate of expansion of the flame front in a combustion reaction. Whereas flame velocity is generally used for a fuel, a related term is explosive velocity, which is the same relationship measured for an explosive. Combustion engineers differentiate between the laminar flame speed and turbulent flame speed.