摘要
The supercritical carbon dioxide(S-CO_(2))cooling wall in coal-fired boiler suffers from severe fragile crisis due to the high temperature of S-CO_(2).The analysis of both heat transfer at process scale and cooling wall arrangement at component scale were carried out in present work.At the process scale,the difference in heat transfer performance between the smooth tube and the rifled tube were identified,especially the location of maximum outer wall temperature of cooling wall.The 1-D mathematical model for thermal-hydraulic analysis of S-CO_(2)furnace cooling wall tubes was then developed.At the component scale,the coupled model of combustion and S-CO_(2)heat transfer is employed for studying the thermal-hydraulic performance of rifled-spiral(R-S)and smooth-spiral(S-S)cooling wall arrangements.The maximum outer wall temperature of R-S cooling wall is 16.38℃lower while the pressure drop increases by 2.33 times compared with the S-S cooling wall.Considering the pressure drop penalty on cycle efficiency of S-CO_(2)boiler power system,the R-S cooling wall is not recommended,while the S-S cooling wall should be carefully arranged in S-CO_(2)boilers.
基金
This work was supported by the National Key Research and Development Program of China under grant number of 2017YFB0601803
the National Natural Science Foundation of China under grant number of 51721004.
