Which term describes the air that assists in the combustion process after the ignition point?

The term that describes the air that assists in the combustion process after the ignition point is secondary air. Secondary air is introduced into the combustion chamber after the initial fuel-air mixture has ignited, helping to complete the combustion process. It plays a crucial role in enhancing combustion efficiency by providing additional oxygen, which helps to burn off any remaining fuel that was not fully combusted during the initial stage.

In combustion systems, different types of air are introduced at various stages. Primary air is the air that mixes with the fuel before ignition occurs, while tertiary air, when referred to, typically indicates air introduced even later in the combustion process to optimize thermal efficiency and reduce emissions. Venturi air involves a specific mechanism related to the flow of air and fuel in a venturi tube but is not a standard classification used to describe phases of combustion air.