A New Method for Calculating Excess Air Ratio

The excess air ratio indicates the excess of supporting air for fuel combustion, and is an important control parameter in operation adjustment for combustion equipment. In the present methods for calculating excess air ratio, the conventional method is simple but imprecise, and the improved method is accurate but complicated. Based on the definition and solution model of excess air volume, a new method for calculating excess air ratio was derived, and the concept of fuel component factor was proposed. Finally, the new method was compared with the current methods through fuel composition and combustion data. The results show that the conventional method is only suitable for the fuel whose fuel component factor is close to zero. The new method is obtained by fuel composition factor and flue gas composition, which can not only guarantee the accuracy of the solution, but also simplify the solution process, and it is a general calculation model that can be applied to any fuel.