Evaluation of thermophoretic effects on graphite dust coagulation in high-temperature gas-cooled reactors  

作　　者：Kaiyuan Wang Suyuan Yu Wei Peng 

机构地区：[1]Center for Combustion Energy,Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China [2]Institute of Nuclear and New Energy Technology,Advanced Nuclear Energy Technology Cooperation Innovation Center,Key Laboratory of Advanced Nuclear Engineering and Safety of Ministry of Education,Tsinghua University,Beijing 100084,China

出　　处：《Particuology》2020年第4期45-52,共8页颗粒学报（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(Grant No.51676112);the National Key Research&Development Program of China(Grant No.2016YFC0202700);the National Science&Technology Major Project(Grant No.ZX069);Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education.We also thank Prof.David Christopher for editing the English.

摘　　要：In high-temperature gas-cooled reactors,graphite dust particles within the reactor core and the heat transfer equipment experience large temperature gradients.Under such conditions,thermophoresis may play an important role in determining aerosol evolution.This study presents a theoretical and numerical analysis of the thermophoretic effects on aerosol coagulation within these reactors.The coagulation rates for Brownian versus thermophoretic coagulation are calculated and compared for various temperature gradients.Our results show that thermophoretic coagulation dominates over Brownian coagulation for large temperature gradients.We defined an enhancement factor to evaluate the role of thermophoretic coagulation under various reactor conditions.The enhancement factor increased dramatically with increasing temperature gradient,decreasing pressure and increasing particle diameter,but was not very sensitive to temperature change.The time evolution of the particle size distribution related to combined Brownian and thermophoretic coagulation was simulated using a log-skew-normal method of moments.The simulation results indicate that aerosol evolution can be strongly accelerated by thermophoretic coagulation under large temperature gradients.

关 键 词：Graphite dust High-temperature gas-cooled reactor Thermophoretic coagulation Log-skew-normal method of moments Particle size distribution 

分 类 号：O17[理学—数学]