摘要
用分子动力学模拟了超临界Lennard-Jones(L-J)流体在微通道内的剪切应力与速度分布。利用经典流体力学理论中剪切应力和速度分布之间的关系式,得到了超临界氩与超临界氦在不同温度和密度条件下的动力粘度。结果说明,L-J流体模型得到的超临界氩的粘度与美国国家标准局(NIST)公布的数据十分接近,超临界氦的粘度与NIST中的粘度数据具有相同的数量级,但是数值稍有偏差,说明氦这种量子流体,单纯以L-J流体势能模型为基础是不完全的,需要在此基础上进行量子效应的修正。
Shearing stress and velocity distribution of supercritical Lennard-Jones（L-J） fluids with different temperatures flowing in micro channel were obtained by molecular dynamics simulation. The kinematics viscosities of supercritical argon and supercritical helium in different temperature and density ranges were calculated by expression which describing the relationship between shearing stress and velocity distribution. The results show that the viscosity values of supercritical argon given by L-J fluid model are close to the values published by the National Institute of Standards and Technology（NIST）. The viscosity values of supercritical helium given by L-J fluid model have the same order as the values published by the NIST, but a little difference between them can be found. All the simulation results show that the L-J model is not completely correct for the quantum fluid such as helium, therefore the quantum effect should be taken into account when the quantum fluid is studied.
出处
《低温工程》
CAS
CSCD
北大核心
2008年第4期32-37,共6页
Cryogenics
基金
上海市重点学科建设项目(P1401)资助
上海工程技术大学博士启动基金资助项目(校启08-6)
关键词
L-J流体
分子动力学
超临界
粘度
量子效应
L-J fluid
molecular dynamics
supercritical
viscosity
quantum effect
