HORTICULTURE

Detailed explanation-1: -Primary air provides a percentage of the combustion air, but more importantly, controls the amount of fuel that can be burned. Secondary air improves combustion efficiency by promoting the fuel to burn completely. Power burners generally do not require secondary air.

Detailed explanation-2: -The secondary air is the postcombustion air injected into the upper part of the combustion chamber and is necessary for completing the combustion process. Together with the recirculated gas it takes part in temperature and oxygen concentration controls.

Detailed explanation-3: -Simply put, it is the ratio (usually of mass) between air and flammable gas or vapor at which complete combustion or chemical combination takes place. Approximately 14.5 kg of air is required for complete combustion of 1 kg of gasoline. Therefore, one can say that the air/fuel mixture is approximately 14.5:1.0.

Detailed explanation-4: -In petrol engine vehicles, secondary air injection is a proven method of reducing harmful substance emissions during cold starting. A petrol engine needs a “rich mixture” for reliable cold starting. This means that the fuel/air mixture contains excess fuel.

Detailed explanation-5: -For adequate combustion to happen, you require combustion air, excess air, and dilution air when using a draft device. Combustion air is made up of primary and secondary air when speaking about perfect combustion. Since we strive for complete combustion in the real world, excess air is added to ensure combustion.