Numerical study on a cryogenic treatment process with nearzero loss of cold energy

27th International Cryogenics Engineering Conference and International Cryogenic Materials Conference 2018

Zhao, Y.H.^1^2 ; Chen, L.B.^1 ; Guo, J.^1 ; Gu, K.X.^1 ; Zhou, Y.^1 ; Wang, J.J.^1^2

Chinese Academy of Sciences Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Beijing

100190, China^1

University of Chinese Academy of Sciences, Beijing

100049, China^2

关键词: Cold energy;    Gas vents;    Operational characteristics;    Recovery rate;    Soaking time;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/502/1/012158/pdf
DOI  :  10.1088/1757-899X/502/1/012158

来源: IOP

【 摘 要 】

Cryogenic treatment generally means that the material is held at a cryogenic equipment for a given soaking time and temperature, then heated to room temperature to improve the mechanical properties. In this paper, a cryogenic treatment process with near-zero loss of cold energy is proposed, and then an equipment is designed according to the proposed process. The operational characteristics of the designed equipment, such as temperature field and cold energy recovery rate, are verified by using CFD. The calculations show that the recovery rate of cold energy can get close to 100%, but it is difficult for materials to be processed according to a given process because of the uncontrolled diffusion of heat. Then, this paper further discusses improvement schemes: replenishing a certain amount of cold energy in the space where the material is cryo-Treated, and setting some gas vents at a certain position in the middle of the device to reduce the amount of air that transports cold energy.