| Abstract
| - 1-Heptanol flow in irregularly shaped surface grooves in Pd-coatedCu is shown to be an example ofPoiseuille flow with simple Washburn kinetics of the formz2 = C(γ/μ)t,where γ is the liquid surface tension,μ is the viscosity, and C is a function of the groovedimensions and the contact angle θ. A shapeindependentexpression is derived for the geometric factor,C(S,w,θ) = (Scos(θ) − w)/4π, where w is the widthof thegroove at the surface and S is the arc length, or totallength of groove surface in a plane perpendicularto the groove axis. This expression is general for any grooveshape and reduces to the form derivedpreviously for V-shaped grooves. Along with scanning electronmicroscopy, three different techniques,stylus profilometry, laser profilometry, and optical interferometry,were used to characterize the groovegeometry, especially to determine S and w.While reasonable agreement is obtained betweenliteraturevalues of γ/μ and values obtained from the experimental kinetics,the main conclusion is that measurementof the groove dimensions is the main limitation to experimentalverification of the form of C and to theuse of the kinetics of groove flow as an absolute measure of the factorγ/μ. However, we show that if Cis calibrated for a specific groove with a known liquid, the kineticsof capillary flow in open surface groovesfurnishes a simple, easily applied method for measurement of thesurface tension-to-viscosity ratio, γ/μ.
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