Nikolaus Adams – författare

Micro and nano-fluidics concerns fluid dynamics occurring in devices or flow configurations with minimum design length measured in micrometers or smaller. The behavior of fluids at these scales is quite different from that at the macroscopic level due to the presence of surface tension effects, wetting phenomena, Brownian diffusion and hydrodynamic interactions with immersed particles and microstructures. These effects cannot be generally represented in a classical homogeneous continuum framework. However, this triggers the development of new tools to investigate and simulate problems at the meso-scopic level.This book contains a collection of works presented at the IUTAM Symposium on Advances on Micro and Nano-fluidics held in Dresden in 2007. It covers several subjects of wide interest for micro and nano-fluidics applications focusing on both, analytical and numerical approaches. Topics covered in particular include multi-scale particle methods for numerical simulations, liquid-wall interactions and modeling approaches, modeling of immersed nano-scale structures, organized flow behavior at micro and nano-scales, and methods for control of micro- and nano-scale flows.

Turbulent ?ows are ubiquitous in most application ?elds, ranging from - gineering to earth sciences and even life sciences. Therefore, simulation of turbulent ?ows has become a key tool in both fundamental and applied - search. The complexity of Navier-Stokes turbulence, which is illustrated by the fact that the number of degrees of freedom of turbulence grows faster 11/4 thanO(Re ), where Re denotes the Reynolds number, renders the Direct Numerical Simulation (DNS) of turbulence inapplicable to most ?ows of - terest. To alleviate this problem, truncated solutions in both frequency and wavenumbermaybesought,whosecomputationalcostismuchlowerandmay ideally be arbitrarily adjusted. The most suitable approach to obtain such a low-cost three-dimensional unsteady simulation of a turbulent ?ow is Large- EddySimulation(LES),whichwaspioneeredtocomputemeteorological?ows in the late 1950s and the early 1960s. One of the main issues raised by LES is a closure problem: because of the non-linearity of the Navier-Stokes equations, the e?ect of unresolved scales must be taken into account to recover a reliable description of resolved scales of motion (Chap. 2).This need to close the governing equations of LES has certainly been the main area of investigation since the 1960s, and numerous closures,alsoreferredtoassubgridmodels,havebeenproposed. Mostexisting subgrid models have been built using simpli?ed viewsof turbulence dynamics, the main physical phenomenon taken into account being the direct kinetic - ergycascade from largeto small scales that is observed in isotropic turbulence and high-Reynolds fully developed turbulent ?ows. The most popular pa- digm for interscale energy transfer modeling is subgrid viscosity (Chap.

Micro and nano-fluidics concerns fluid dynamics occurring in devices or flow configurations with minimum design length measured in micrometers or smaller. The behavior of fluids at these scales is quite different from that at the macroscopic level due to the presence of surface tension effects, wetting phenomena, Brownian diffusion and hydrodynamic interactions with immersed particles and microstructures. These effects cannot be generally represented in a classical homogeneous continuum framework. However, this triggers the development of new tools to investigate and simulate problems at the meso-scopic level.This book contains a collection of works presented at the IUTAM Symposium on Advances on Micro and Nano-fluidics held in Dresden in 2007. It covers several subjects of wide interest for micro and nano-fluidics applications focusing on both, analytical and numerical approaches. Topics covered in particular include multi-scale particle methods for numerical simulations, liquid-wall interactions and modeling approaches, modeling of immersed nano-scale structures, organized flow behavior at micro and nano-scales, and methods for control of micro- and nano-scale flows.