Abstract: In a research on a 650 MW supercritical boiler，taking closing-to-wall air distribution scheme and distribution ratio of internal and external secondary air as variables，a proposed solution to high-temperature corrosion is adjusting air distribution proportion of closing-to-wall air and internal/external secondary air.According to the research results，the variation trends of CO volume fractions near the wall obtained by simulation and test were convergent，while the mathematical model was more accurate.When the ratios of secondary air in furnaces on two sides were adjusted to 0.22 and 0.32，their influence on CO distribution near the wall was minor，while the unburned carbon in fly ash and NOx mass concentration at the furnace outlet showed a slight fluctuation with the adjustment of the ratio.When the ratio reached 0.37，the accumulation area and volume fraction of CO reduced dramatically，while the mass concentration of NOx at the furnace outlet had a further increase.To alleviate high-temperature corrosion，judgment should be made in line with the actual situation of furnace reconstruction projects.

Key words: high-temperature corrosion, numerical simulation, closing-to-wall air, collaboration, anticorrosion