Abstract: In order to study the efficiency of radiative heat transfer in the coal-fired furnace,and achieve the aim of saving energy and reducing pollutant emissions,this paper presented an experimental measurement method for radiation entropy generation and radiation exergy in large-scale furnaces.The method was applied in a 670 t/h coal-fired boiler of a 200 MW generator unit.The radiative images in the furnace were captured by CCD cameras installed on the boiler.The temperature distributions and radiative properties in three sections of the furnace were reconstructed by the solution of inverse radiation problem.And then,experimental results of radiative entropy generation,dimensionless radiative entropy generation,and radiative exergy of pulverized coal combustion medium and water cooling wall in the furnace were obtained.The effects of standard deviation of temperature distribution in furnace and radiative heat flux of wall on radiative entropy generation and radiative exergy were analyzed.The results show that with the increase of standard deviation of temperature distribution in coal-fired boilers,the irreversibility of absorption,emission and scattering process of pulverized coal combustion medium increase gradually,and the radiation heat transfer efficiency decreases gradually,and generated by combustion medium,the radiative entropy generation increases from 419 W/K to 629 W/K and the dimensionless radiative entropy generation increases from 0.048 to 0.067.With the increase of heat flow on water-cooled wall,the irreversibility of radiation heat transfer process on water-cooled wall increases gradually,and the radiative heat transfer efficiency decreases gradually,so the radiative entropy generation generated by the water cooling wall increases from1. 566 k W/K to 4. 575 k W/K and the dimensionless radiative entropy generation increases from 0.258 to 0.346.In the burner area of the furnace,due to the relatively highest combustion temperature,the radiation heat exchange process is the most intense,leading to the most available work,so the radiative exergy is the largest.In the furnace exit area where the temperature is relatively lowest,the radiation heat transfer process is relatively weakest,and the available work is relatively least,so the radiation exergy is relatively minimal.It can be seen that for the practical furnace,improving the uniformity of the temperature field in the furnace,especially increasing the uniformity of the temperature field in the furnace burner region,is of great significance for improving the radiation heat transfer efficiency of the coal-fired furnace.