Compared with coal-fired steam boilers in power plant

supercritical carbon dioxide(S-CO_2) boilers have higher working fluid parameters and poorer cooling capacity to the wall

which makes the S-CO2 boilers' structural design more challenging. In this paper

by taking the layout scheme of a 5 MW S-CO_2 experimental boiler as an example

the equations of loop flow and pressure difference for the gas cooled wall of the boiler are established

the gas flow and temperature is solved using the quasi Newton method

and the wall metal temperature is calculated according to thermal load. The calculation results show that

the relative deviation of flow rate in the gas cooled wall is less than 7%

and the metal temperature is within the allowable range of material strength. The boiler design scheme is proved to be safe and reliable. The research results have certain significance to the subsequent product improvement and optimization and large-scale.