Studies of fluid transport in micro- and nano-systems have recently　received great attention due mainly to the modern development of micro- and　nano-technologies. As the spatial scales of the flow approach the molecular size, the continuum　assumption breaks down and the molecular effects cannot be ignored. Atomistic　descriptions cannot treat large domains due to the immense number of computational molecules　involved and the multiscale simulation capable of coupling molecular dynamics with the　continuum hydrodynamics is an efficient way to model the micro- and nano-fludics. A framework for continuum and molecular dynamics hybrid multiscale method　has been recently developed to simulate micro- and nano-fluid flows. In this　approach, The continuum Navier-Stokes equation is used in one flow region and atomistic　molecular dynamics in another. The spatial coupling between two methods is achieved　through the constrained dynamics in an overlap region.

The proposed multiscale method has been validated in simple fluid flows,　including sudden-start Couette flow and channel flow with nano-scale wall roughness,　showing quantitative agreement with results from analytical solutions and full　molecular dynamics simulations. The hybrid method is then used to study the　singularity problem in the driven cavity. Continuum equations predict an infinite force due to　stress singularity. Following the stress over more than six decades in length in　systems with characteristic scales of millimeters and milliseconds allows us to resolve　the singularity and determine the force for the first time. The speedup over　pure atomistic calculation is more than fourteen orders of magnitudes. We find a　university dependence on the macroscopic Reynolds number, and large atomistic effects　that depend on wall velocity and molecular interactions.

The numerical algorithms pertinent to multiscale time and fast convergence　to steady states will be presented. Applications of the multiscale method for moving　contact lines, polymeric flows, thermal flows and electrokinetic flows will be　discussed.

陈十一教授简介：目前任北京大学工学院首任院长,美国约翰?霍普金斯大学讲席教授.陈十一教授是北京大学首批"长江学者"特聘教授，国家杰出青年基金获得者，美国物理学会fellow，美国Los Alamos国家实验室Fellow，英国物理学会Fellow。两次获得美国研究和发展杂志年度100奖。

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