What is the term for the air mixed with natural gas in a burner?

The term for the air mixed with natural gas in a burner is known as primary air. Primary air is specifically the air that is introduced into the fuel before combustion occurs, resulting in a mixture that can be ignited. This mixture is crucial for achieving efficient combustion because it provides the necessary oxygen for the natural gas to combust properly.

In systems that utilize combustion, managing the proportion of primary air is vital for ensuring that the gas burns efficiently and cleanly, thus minimizing pollutants and optimizing energy output. The correct balance of primary air leads to better performance and efficiency in heating applications.

The other terms refer to different aspects of air usage in combustion processes but do not apply in this context. Combustion air generally refers to the overall air required for the combustion process, which includes not just the primary air but also any excess air added for complete combustion. Excess air pertains specifically to additional air provided beyond the stoichiometric amount needed for combustion, which helps ensure complete combustion but does not define the initial air-fuel mixture. Dilution air is introduced after combustion and is typically used for cooling or reducing the concentration of combustion gases, not for mixing with the fuel before ignition.