Effect roughness

Simon, H. and Bulskamper, A., On the Evaluation of Reynolds Numbei and Relative Surface Roughness Effects on Centrifugal Compressor Per formance Based on Systematic Experimental Investigation, ASME 8J-C,1 118, New York American Society of Mechanical Engineers, 1983. 

Surface roughness effects in inorganic primer films... 

Medwell, J. O. and A. A. Nicol, Surface Roughness Effects on Condensate Films, ASME-AlChE Heat Trans. Conference and Exhibit, Los Angeles, California, Aug. (1965), Paper No. 65-HT-43. 

Fig. 28—Different stages in transition of lubrication regimes, (a) Full-film lubrication with film thickness much larger than roughness h/cr> ). (b) Surfaces are separated but roughness effect becomes significant (5>/i/cr>3). (c) Asperities interfere with each other but hydrodynamic films carry the most load (h/cr 3). (d) Typical mixed lubrication with load shared by lubrication and asperity (h/cr<3). (e) Boundary lubrication when asperities carry the most part of load (h/a-<0.S).

Tzeng, S. T. and Saibel, E., "Surface Roughness Effect on Slider Bearing Lubrication, ASLE Trans., Vol. 10, 1967, p. 334. 

Figure 2.3 Model geometry used for the study of surface-roughness effects on rarefied gas flows in micro channels.

Jackson et al. (J2), 1951 Experimental study of film flow inside tube with counter-flow of gas. Film surface velocity deduced from pressure drop readings in gas stream, neglecting wave roughness effects. Surface velocities appear to exceed the theoretical values in the wavy flow regime. 

PORE ROUGHNESS EFFECTS ON HIGH-FREQUENCY PERMEABILITY... 

Both of these methods may be applied to nonplanar electrodes if the results are obtained at electrolysis times sufficiently short that the diffusion layer remains thin in comparison to the radius of curvature of the nonplanar electrode surface. For example, the spherical hanging-mercurcy-drop electrode provides chronoamperometric data that deviate less than 1-2% from the linear-diffusion Cottrell equation out to times of about 1 s. With solid wire electrodes of cylindrical geometry, similar conclusions apply, but at short times surface roughness effects yields a real surface area that is larger than the geometric area. 

Farm and Avnir [113] were the first to use fractal geometry to determine effects of surface morphology on drug dissolution. This was accomplished by the use of the concept of fractal reaction dimension dr [114], which is basically the effective fractal dimension of the solid particle toward a reaction (dissolution in this case). Thus, (5.7) and (5.8) were modified [113] to include surface roughness effects on the dissolution rate of drugs for the entire time course of dissolution... 

Hering, R. G., and T. F. Smith Surface Roughness Effects on Radiant Transfer between Surfaces, Int. J. Heat Mass Transfer, vol. 13, p. 725, 1970. 

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