As an important component of tokamaks,the divertor is mainly responsible for extracting heat and helium ash,and the targets of the divertor need to withstand high heat flux of 10 MW m-2 for steady-state operation.In t...As an important component of tokamaks,the divertor is mainly responsible for extracting heat and helium ash,and the targets of the divertor need to withstand high heat flux of 10 MW m-2 for steady-state operation.In this study,we proposed a new strategy,using microchannel cooling technology to remove high heat load on the targets of the divertor.The results demonstrated that the microchannel-based W/Cu flat-type mock-up successfully withstood the thermal fatigue test of 1000 cycles at 10 MW m^(-2)with cooling water of 26 l min^(-1),30°C(inlet),0.8 MPa(inlet),15 s power on and 15 s dwell time;the maximum temperature on the heat-loaded surface(W surface)of the mock-up was 493°C,which is much lower than the recrystallization temperature of W(1200°C).Moreover,no occurrence of macrocrack and‘hot spot’at the W surface,as well as no detachment of W/Cu tiles were observed during the thermal fatigue testing.These results indicate that microchannel cooling technology is an efflcient method for removing the heat load of the divertor at a low flow rate.The present study offers a promising solution to replace the monoblock design for the EAST divertor.展开更多
基金financial support from the National MCF Energy R&D Program(No.2018YFE0312300)National Natural Science Foundation of China(No.51706100)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK20180477)Fundamental Research Funds for the Central Universities(No.30918011205)。
文摘As an important component of tokamaks,the divertor is mainly responsible for extracting heat and helium ash,and the targets of the divertor need to withstand high heat flux of 10 MW m-2 for steady-state operation.In this study,we proposed a new strategy,using microchannel cooling technology to remove high heat load on the targets of the divertor.The results demonstrated that the microchannel-based W/Cu flat-type mock-up successfully withstood the thermal fatigue test of 1000 cycles at 10 MW m^(-2)with cooling water of 26 l min^(-1),30°C(inlet),0.8 MPa(inlet),15 s power on and 15 s dwell time;the maximum temperature on the heat-loaded surface(W surface)of the mock-up was 493°C,which is much lower than the recrystallization temperature of W(1200°C).Moreover,no occurrence of macrocrack and‘hot spot’at the W surface,as well as no detachment of W/Cu tiles were observed during the thermal fatigue testing.These results indicate that microchannel cooling technology is an efflcient method for removing the heat load of the divertor at a low flow rate.The present study offers a promising solution to replace the monoblock design for the EAST divertor.