...Pooja Thakur; Shruti Gautam; Aruna Thakur The objective of the study is to thoroughly analyze the flow and heat transfer of Bingham plastic fluids through an array of uniformly gapped rough surface cylinders embedded between two confined boundaries. Radial notches are used as the surface roughness...

... - ɛ model to describe the gas phase turbulence, which includes the suppression and enhancement effects due to the presence of particles. For comparison, a two-layer model was also implemented since it has the capability to include surface roughness. The current study examines the predictions...

... surface roughness In recent years, microfluidic systems such as lab-on-a-chip devices and micro total analysis systems have attracted enormous attention for such applications as chemical and biological analyses, drug delivery, DNA hybridization, and so on. Microfluidic systems have many advantages...

...N. Rostamy; D. J. Bergstrom; D. Sumner; J. D. Bugg The effect of surface roughness on the mean velocity and skin friction characteristics of a plane turbulent wall jet was experimentally investigated using laser Doppler anemometry. The Reynolds number based on the slot height and exit velocity...

... in the overlap region is carried out by the Izakson-Millikan-Kolmogorov hypothesis. The velocity profiles and skin friction are shown to be governed by universal log laws as well as by universal power laws, explicitly independent of surface roughness, having the same constants as a fully smooth surface wall jet...

... conclusions can be made. 1 As the surface roughness of the compressor cascade blade increases, the axial velocity is decreased, and deviation and loss are increased. 2 With increasing roughness k s / c from 0.0006 to 0.0090, 0.00150, 0.00213, and 0.00425, the axial velocity ratio decreases...

... of the surface roughness profile and builds on previous work utilizing moments of the surface statistics. A relationship is given for the equivalent sandgrain roughness height as a function of the root-mean-square roughness height and the skewness of the roughness probability density function. Boundary layer...

..., which develops due to the nonuniformity of the form of EDLs and surface roughness, generates a nonuniform flow field in the bulk region above the obstacle. The mole fraction distributions (Fig. 7c ) show that for the strong solution the bulk fluid is electrically neutral except near the obstacle...

... in the water. 12 06 2007 03 05 2008 09 01 2009 bubbles chemical analysis hardness stainless steel surface roughness tempering ultrasonic applications vibrations wear cavitation erosion bubble dynamics thermal effect ultrasonic vibration cavitation It has been...

...Prashant R. Waghmare; Sushanta K. Mitra The present study is carried out to investigate the influence of surface roughness in combined electro-osmotic and pressure-driven flow in microchannel. Two-dimensional theoretical model is developed to predict the behavior of velocity profiles in rough...

... the effect of surface roughness on the impact dynamics of single cryogen droplets falling on skin models of various roughnesses ( 0.5 – 70 μ m ) . We first develop a theoretical model to predict the maximum spread diameter ( D m ) following droplet impingement based on a similarity approximation...

...Noor Afzal The present work deals with four new alternate transitional surface roughness scales for description of the turbulent boundary layer. The nondimensional roughness scale ϕ is associated with the transitional roughness wall inner variable ζ = Z + ∕ ϕ , the roughness friction Reynolds...

... , in terms of new scaling parameter, viz., the roughness Reynolds number Re ϕ = Re ∕ ϕ (where ϕ is a nondimensional roughness scale), is a universal relation for all kinds of surface roughness. This means that Prandtl’s smooth pipe friction factor relation would suffice provided that the traditional Reynolds...

... -type roughness in the turbulent boundary layer. Legend same as in Figs. 1a 1b 1c 1d . 29 01 2006 04 03 2007 boundary layer turbulence rough surfaces surface roughness friction wakes nonlinear equations numerical analysis The power law velocity profile in a wall...

... on the material surface. An increase in compressive residual stress was expected at longer peening exposure times and shorter standoff distances when material removal occurred. Results also showed that the changes in surface roughness are directly influenced by the kinetic energy that has been transferred...

...A. S. Ziarani; A. A. Mohamad A molecular dynamics simulation of flow over two side-by-side cylinders with atomically rough surfaces is presented. The model is two-dimensional with 3 × 10 5 liquid argon atoms. The surface roughness is constructed by external protrusion of atoms on the surface...

... reduction lubrication surface roughness Water and water-based lubricants, such as emulsions, are widely used in metalworking lubrication and journal bearing lubrication ( 1 2 3 4 5 ). The good lubricating properties of water-based lubricants have been studied for many years ( 1 ). In most...

...Stephen T. McClain; S. Patrick Collins; B. Keith Hodge; Jeffrey P. Bons The discrete-element surface roughness model is used to provide insight into the importance of the mean elevation of surface roughness in predicting skin friction over rough surfaces. Comparison of experimental data...

...Qiang Zhang; Matt Goodro; Phillip M. Ligrani; Ricardo Trindade; Sri Sreekanth The effects of surface roughness on the aerodynamic performance of a turbine vane are investigated for three Mach number distributions, one of which results in transonic flow. Four turbine vanes, each with the same shape...

... larger than for the smooth surface, and for each rough surface, the value of Π is observed to increase as the roughness shift increases. This is one example of the effect of surface roughness extending into the outer region. The values of the skin friction coefficient, C f...