Slip-length measurement of confined air flow using dynamic atomic force microscopy

Abdelhamid Maali (1) , Bharat Bhushan (2)

1 CPMOH - Centre de physique moléculaire optique et hertzienne
2 NLB2 - Nanoprobe Laboratory for Bio- and Nanotechnology and Biomimetics

We present an experimental measurement of the slip length of air flow close to solid surfaces using an atomic force microscope (AFM) in dynamic mode. The air was confined between a glass surface and a spherical glass particle glued to an AFM cantilever. The Knudsen number was varied continuously over three decades by varying the distance between the two surfaces. Our results show that the effect of confining the air is purely dissipative. The data are described by an isothermal Maxwell slip-boundary condition, and the measured slip-length value was 118 nm.

Mots clés: 47.10.ad; Navier-Stokes equations; 47.45.Gx; Slip flows and accommodation; 83.50.Lh; Slip boundary effects (interfacial and free surface flows) (see also 47.45.Gx Slip flows and accommodation in fluid dynamics); 83.50.Rp; Wall slip and apparent slip

Domaines: Dynamique des Fluides [physics.flu-dyn]

Abdelhamid Maali, Bharat Bhushan. Slip-length measurement of confined air flow using dynamic atomic force microscopy. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2008, 78 (2), pp.027302 (1-4). ⟨10.1103/PhysRevE.78.027302⟩. ⟨hal-00762535⟩