Thermophoresis of nanoparticles hotter/colder than the surrounding dilute gases

作     者：Junjie Su Jie Cui Jun Wang Guodong Xia Junjie Su;Jie Cui;Jun Wang;Guodong Xia

作者机构：MOE Key Laboratory of Enhanced Heat Transfer and Energy ConservationBeijing Key Laboratory of Heat Transfer and Energy ConversionBeijing University of TechnologyBeijing 100124China 

出 版 物：《Particuology》 (颗粒学报（英文版）)

年 卷 期：2022年第20卷第4期

页      面：95-102页

核心收录：

学科分类：08[工学] 080103[工学-流体力学] 0817[工学-化学工程与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：This work is supported by the National Natural Science Foun-dation of China(grants Nos.51776007) Beijing Nova Program of Science and Technology(No.Z19100001119033) Youth Tal-ent Support Program of Beijing Municipal Education Committee(No.CIT&TCD201904015). 

主　　题：Thermophoresis Particle temperature Nanoparticles Free molecule regime 

摘      要：Aerosol particles suspended in a diluted gas with non-uniform temperature distribution are expected to experience a thermophoretic force.In theoretical treatment of thermophoresis,it is usually assumed that the particle temperature is equal to the surrounding gas temperature.However,this might not always be the case.In some particular applications,the particle temperature can significantly differ from the gas temperature.In the present paper,we theoretically investigate the effect of the particle tempera-ture on the thermophoresis of nanoparticles in the free molecule regime.Theoretical formulas for the thermophoretic force and thermophoretic velocity are obtained based on the gas kinetic theory.As exam-ples,a spherical Ag nanoparticle suspended in a dilute He gas is considered,and the Rudyak-Krasnolutski potential is employed to model the gas-particle interaction.It is found that the influence of the particle temperature on the thermophoresis of nanoparticles can be significant.With increasing particle size,the error due to the equal gas-particle temperature assumption can be neglected.