Search

Your search keyword '"Feng, Yongjin"' showing total 144 results
Start Over Author "Feng, Yongjin"
144 results on '"Feng, Yongjin"'

26. Investigation of Wall Effect on Packing Structures and Purge Gas Flow Characteristics in Pebble Beds for Fusion Blanket by Combining Discrete Element Method and Computational Fluid Dynamics Simulation.

Author

Gong, Baoping, Cheng, Hao, Zhou, Bing, Yan, Juemin, Wang, Long, Zhang, Long, Feng, Yongjin, and Wang, Xiaoyu

Subjects
COMPUTATIONAL fluid dynamics, DISCRETE element method, FUSION reactor blankets, PEBBLES, GAS flow, NUCLEAR fusion, PRESSURE drop (Fluid dynamics)
Abstract

In a tritium-breeding blanket of a fusion reaction, helium, used as a tritium-purging gas, will purge the tritium breeder pebble beds to extract the tritium in blanket. The purge gas flow characteristics will affect the tritium extraction efficiency. The effect of the fixed wall on the pebble packing structures and purge gas flow characteristics was investigated by combining the discrete element method (DEM) and computational fluid dynamics (CFD) method. The results indicate that the fixed wall leads to a regular packing of the pebbles adjacent to the fixed wall in association with drastic fluctuations in the porosity of the pebble bed, which can affect the purge gas flow behaviors. Further analyses of helium flow behaviors show that the helium pressure in the pebble bed decreases in a linear manner along the flow direction, whereas the pressure drop gradient of helium increases gradually with an increase in the packing factor. The reduction in porosity in the pebble bed leads to a notable escalation in helium flow velocity. Concerning the direction perpendicular to the helium gas flow, the evolution of the cut-plane averaged velocity of helium is similar to that of the porosity, except in the region immediately adjacent to the wall. The pressure drop and flow characteristics obtained in this study can serve as input for the thermohydraulic analysis of the tritium blowing systems in the tritium-breeding blanket of a fusion reactor. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

31. Current progress of Chinese HCCB TBM program

Author

Feng, Kaiming, Wang, Xiaoyu, Feng, Yongjin, Chen, Yanjing, Zhao, Zhou, Li, Zaixin, Wang, Pinghua, Wang, Qijie, Ye, Xingfu, Zhao, Fengchao, Zhang, Long, Wang, Feng, Chao, Qixiang, Wu, Xinghua, Wang, Yanlin, Wang, Jun, Liu, Yang, Yang, Li, Chen, Yinfen, Yu, Guo, Liu, Jie, Wang, Xiaoyong, Zhang, Mingchun, Gong, Baoping, Zhang, Guoshu, Hu, Gang, Zhou, Bin, Liao, Hongbin, Bai, Meng, Pan, Chuanhong, Duan, Xuru, and Xing, Chao

Published
2016
Full Text
View/download PDF

40. Microstructure Change, Nano-Hardness and Surface Modification of CN-G01 Beryllium Induced by Helium Ions.

Author

Cui, Minghuan, Jin, Peng, Shen, Tielong, Zhu, Yabin, Pang, Lilong, Wang, Zhiguang, Luo, Xiaofang, Feng, Yongjin, and Gong, Baoping

Subjects
BERYLLIUM, HELIUM ions, ELECTRON microscope techniques, NUCLEAR energy, TRANSMISSION electron microscopy, SCANNING electron microscopy
Abstract

The helium effects in Chinese developed CN-G01 beryllium are important issues for its use in nuclear energy systems. In this work, the CN-G01 beryllium samples were irradiated with helium ions to fluences of 5.0 × 1016 ions/cm2 to 1.0 × 1018 ions/cm2 at room temperature and investigated by techniques of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nano-indentation. It was found that the irradiation induced hardening of beryllium and the nano-hardness of the samples increased with increasing fluence of 5.0 × 1016 ions/cm2 to 1.0 × 1017 ions/cm2. When the fluence reached 5.0 × 1017 ions/cm2 and 1.0 × 1018 ions/cm2, helium irradiation induced serious surface blistering and its burst. TEM observation found that helium bubbles in the damage peak region became visible when the fluence reached 1.0 × 1017 ions/cm2. With increasing fluence, helium bubbles became larger and connected into large cracks. The underlying physical mechanisms are discussed based on the helium behavior at low temperatures and the contributions of helium induced defects. This work will provide some new understanding on the irradiation resistance of CN-G01 beryllium and the helium effects in beryllium at low temperatures. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results