An explosion or sudden report made by the instantaneous decomposition or combustion of unstable substances; as, the detonation of gun cotton.
This is a supersonic combustion wave. Detonations in gases propagate with velocities that range from 5 to 7 times the speed of sound in the reactants. For hydrocarbon fuels in air, the detonation velocity can be up to 1800 m/s. The ideal detonation speed, known as the Chapman-Jouguet velocity, is a function of the reactant composition, initial temperature and pressure.
Rapid and uncontrolled combustion. Detonation can occur in the cylinder of a spark ignition engine when operating on a fuel of inadequate octane rating, or with ignition timing too far advanced. It is also known as ""pinging"" or ""knocking.""
An explosive reaction that consists of the propagation of a shock wave through the explosive accompanied by a chemical reaction that furnishes energy to sustain the shock propagation in a stable manner, with gaseous formation and pressure expansion following shortly thereafter.
Occurs when hot spots (caused by engine deposits) in the combustion chamber ignites the air and fuel mixture prematurely. Also occurs after combustion if any unburned fuel is left in the combustion chamber. Also known as engine knock. Places great stress on the engine and leads to the destruction of the engine if ignored.
Also called knock, it is a condition in which, after the spark plug fires, some of the unburned air-fuel mixture in the combustion chamber explodes. It increases the mechanical and thermal stresses on the engine.
A violent explosion involving high-velocity pressure waves; in a gasoline engine, the spontaneous combustion of part of the compresses charge after spark occurs. Detonation usually produces a characteristic metallic sound, or knock.
The secondary ignition of the air/fuel mixture in the combustion space causing extreme pressures. Detonation is caused by low gasoline octane ratings, high combustion temperatures, improper combustion chamber shape, too-lean mixtures, etc. Detonation produces dangerously high loads on the engine, and if allowed to continue, will lead to engine failure. Detonation, unlike preignition, requires two simultaneous combustion fronts (fuel burning in two or more places in the combustion chamber at once); whereas preignition occurs when the fuel-air mix ignites (with single burning front) before the spark plug fires. Both preignition and detonation produce an audible "knock" or "ping," but detonation does not produce the rapid "wild pinging" noise that is typically associated with preignition. The extreme pressures of detonation can lead to preignition, but even worse the high temperatures of preignition can cause detonation.
Unusually rapid burning of the fuel mixture, possibly caused by excessive combustion chamber temperatures.
A phenomenon of internal combustion where the compressed air/fuel charge explodes violently instead of burning smoothly, usually due to the creation of a second flame front in the combustion chamber, away from the spark plug. Sometimes resulting in an audible knocking noise but always harmful to the engine.
An exothermic chemical reaction which propagates through reactive material at supersonic speed.
a violent release of energy caused by a chemical or nuclear reaction
the act of detonating an explosive
a chemical reaction given by an explosive substance in which a shock wave is formed
an explosive reaction in which the rate of propagation is higher than the speed of sound in the unreacted medium
a rapid explosion that generates supersonic pressure wave s ( shock wave s) in the surrounding medium
a rapid explosion that generates supersonic pressure waves ( shock waves ) in the surrounding medium
a supersonic combustion event involving a shock wave
a very rapid chemical reaction using oxygen that is contained in the material rather than in the air
Rapid, uncontrolled fuel combustion in the combustion chamber, which can cause engine damage. Usually occurs in heavy load conditions, such as when a trailer is being pulled or the vehicle is climbing a hill. Sometimes audible and described as “knock” or “ping.
Uncontrolled burning of the last portion (end gas) of the air/fuel mixture in the cylinder of a spark-ignition engine. Also know as "knock" or "ping".
Rapid, rattling combustion, also called knocking.
An exothermic chemical reaction that propagates with such rapidity that the rate of advance of the reaction zone into the unreacted material exceeds the velocity of sound in that material; that is, the advancing reaction zone is preceded by a shock wave.
The molecular breakdown of a substance brought about by shock. Initiated by detonator.
Slang for pinking or engine knock (US pinging); uncontrolled secondary explosion in the combustion chamber occurring after the spark.
An extreme rapid decomposition of a material in which the reaction is more than a sonic velocity, for example, high explosives.
A violent chemical reaction within a chemical compound or mechanical mixture evolving heat and pressure. A detonation is a reaction that proceeds through the reacted material toward the un-reacted material at a supersonic velocity. The result of the chemical reaction is exertion of extremely high pressure on the surrounding medium, forming a propagating shock wave that originally is of supersonic velocity. When the material is located on or near the surface of the ground, a crater normally characterizes a detonation. Reference: DoD 6055.9 STD
Also known as engine knocking or pre-ignition, detonation is caused by ignition of the air/fuel mixture in the combustion chamber independent of the spark plug firing This condition is an engine malfunction and can often be eliminated by a regular tune-up
To explode with sudden force.
An extremely rapid exothermic decomposition reaction which proceeds at a rate greater than the speed of sound within the reacting material (unlike DEFLAGRATION). The normal mode of initiation is shock (such as a blasting cap or high level mechanical shock), or from initial combustion which, due to peculiarities of confinement or other circumstances accelerates to such a degree that a shock wave is formed. Behind the shock wave is a reaction zone where material is converted to gaseous products at high temperature and pressure. The flow of the reaction is in the same direction as the propagation.
A condition in which, after the spark plug fires, some of the unburned air-fuel mixture in the combustion chamber explodes spontaneously, set off only by the heat and pressure of air-fuel mixture that has already been ignited. Detonation, or "knock," greatly increases the mechanical and thermal stresses on the engine.
A reaction in which the velocity of the reaction front through the unreached fuel medium is equal to or greater than the speed of sound.
A single nuclear device explosion; one or more comprise a test.
A chemical reaction that propagates at speeds faster than the speed of sound. The shock wave generated by such a reaction produces the typical â€œboomâ€ of a detonation.
Also known as "preignition". Explosive, uneven burning of fuel causing engine knock. In a turbocharged vehicle, this is critical, because the extra added air must be precisely balanced with the proper amount of fuel to cool it, or the friction generated by compressing the air will create too much heat, igniting the fuel prematurely, and resulting in potentially severe damage to the piston, valves, cyllinder wall, head gasket, and an assortment of other components. Sufficient fuel will cool the air inlet charge and prevent detonation. Intercooling also reduced the air inlet charge to help combat this danger. See also: PRE-IGNITION, KNOCK and INTERCOOLER.
Aaaaaaaahhhhhhhhh !!! The Achilles heel of the force fed internal combustion engine. When the flame front travel in the combustion chamber destabilizes and causes preignition - the fuel mix explodes to early in the upward stroke of the piston. Fixes are different piston dome &/or combustion chamber shape, higher octane fuel, retard timing, enrichen mixture, lower compression, lower boost, water injection and/or the only device which noticeably increases power, fit an intercooler
A release of energy caused by the extremely rapid chemical reaction of a substance in which the reaction front advances into the unreacted substance at equal to or greater than sonic velocity.
An unwanted explosion of the air/fuel mixture in the combustion chamber caused by excess heat and compression, advanced timing, or an overly lean mixture. Also referred to as "ping".
A wave that passes along the body of an explosive, instantaneously converting the explosive into gas, e.g., dynamite. An explosion at speeds above 3,300 feet per second.
Uncontrolled combustion of the air / fuel in the cylinder. Primarily caused by the following factors: Boost too high,Ignition too advanced, Intake air temp too high, Also - Detonation will not destroy or adversely affect your turbo, but it will destroy your pistons, con-rods, and maybe crank Also known as "pinging".
Detonation is a process of supersonic combustion in which a shock wave is propagated forward due to energy release in a reaction zone behind it. It is the more powerful of the two general classes of combustion, the other one being deflagration. In a detonation, the shock compresses the material thus increasing the temperature to the point of ignition.