ignição

Ignição refers to the process of initiating combustion in a fuel-air mixture. This initiation typically requires an external energy source to overcome the activation energy barrier of the reaction. The most common form of ignition occurs in internal combustion engines, where a spark plug generates a high-voltage electrical spark to ignite the compressed fuel-air mixture within the cylinder. This controlled explosion drives the piston, producing mechanical work.

In other contexts, ignition can be achieved through various methods. For instance, a match or lighter provides heat to ignite flammable materials like wood or paper. In pyrotechnics and explosives, a fuse or detonator serves as the ignition source. The specific requirements for ignition depend on the fuel's properties, such as its auto-ignition temperature (the temperature at which it will spontaneously combust without an external spark or flame) and its flammability limits (the range of concentrations in air where it can burn). Understanding ignition is crucial in fields ranging from engine design and fire safety to chemical engineering and materials science. Safety protocols are often designed to prevent unintended ignition, while ignition systems are engineered to reliably initiate combustion when and where it is desired.