excess air ratio meaning in English

过量空气比
过量空气系数
过剩空气系数

This paper also analyzes the ash wear mechanism , and then does the effects of low temperature economizer wear five factors : the first is the smoke corridor caused by wear mechanism , the second is the impact on the wall material , and the third is that of flying ash concentration , the fourth of the excess air ratio , and the fifth is the change in the composition of the gas to wear the impact
分析了飞灰磨损的机理，然后分析了影响低温省煤器磨损的5种因素，一是烟气走廊引起磨损的机理；二是管壁材料的影响；三是飞灰浓度的影响；四是过量空气系数的影响；五是烟气成分的变化对磨损的影响。