An explosion or sudden report made by the near-instantaneous decomposition or combustion of unstable substances as, the detonation of gun cotton. Specifically, combustion that spreads supersonically via shock compression
A violent chemical reaction within a chemical compound or mechanical mixture evolving heat and pressure 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 A detonation, when the material is located on or near the ground surface, is normally characterized by a crater
Detonation is the action of causing a device such as a bomb to explode. accidental detonation of nuclear weapons
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
Internal deterioration of aluminum components (usually the piston) resulting from lean mixtures, the collision of multiple flame fronts (excessive timing advance), and poor quality fuel
- an exothermic chemical reaction in which the expanding front travels at supersonic speeds High explosives such as dynamite and ANFOs detonate; fireworks do not
An explosion or sudden report made by the instantaneous decomposition or combustion of unstable substances; as, the detonation of gun cotton
is a rapid explosion of fuel in the cylinder in advance of the spark plug firing It can generate enough heat to melt the pistons and in other ways destroy the engine
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
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
This is the pinging or knocking sound that's sometimes heard while accelerating (See Spark Knock) The noise is the result of erratic combustion inside your engine Instead of burning normally, the fuel explodes in multiple flame front, and the colliding fireballs inside the cylinders shake and rattle the pistons Mild detonation is annoying but it won't hurt anything Severe or prolonged detonation, on the other hand, can ruin your engine If switching to a higher octane fuel doesn't cure the problem, timing adjustments or other repairs may be necessary
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