What Are The Working Principles Of Spark Plugs?

Under the action of high voltage, the air between the center electrode and the side electrode of the spark plug will quickly ionize, forming positively charged ions and negatively charged free electrons. When the voltage between the electrodes reaches a certain value, the number of ions and electrons in the gas increases like an avalanche, causing the air to lose its insulation, and the gap forms a discharge channel, causing a "breakdown" phenomenon. At this point, the gas forms a luminous body, a "spark". As it expands due to heat, a "pop" sound also occurs. The temperature of this kind of electric spark can be as high as 2000~3000℃, which is enough to ignite the mixture in the cylinder combustion chamber.