In order to analyze the ash accumulation degree on convection heating surface of the smokeless temperature measuring point in coal-fired boiler

the heat balance mechanism of heat transfer characteristics of the convection heating surface of the boiler and heat absorption characteristics of the working medium were analyzed. The relationship between the heat transfer coefficient and the temperature difference was obtained

and the ash accumulation degree model on the convection heating surface was established. It is considered that the ash blowing operation on specific heating surface will affect the temperature of flue gas and steam at inlet and outlet of other heating surfaces

while the ash accumulation degree of other heating surfaces remains unchanged. In this paper

the temperature difference of fluid on other heating surfaces caused by soot blowing is proposed to modify the model of ash deposition degree

and the binary linear regression model is established by increasing the load variable

which improves the accuracy of only using the temperature difference to characterize the ash deposition degree. Moreover

by taking a high temperature reheater as an example

numerical simulation is carried out for the superheater and reheater of the boiler

and the result shows that the prediction result of the proposed method for ash accumulation degree of superheat/reheater is more reasonable and accurate.