Experimental study of natural convection heat transfer inside smooth and rough surfaces of vertical and inclined equilateral triangular channels of different inclination angles with a uniformly heated surface are performed. The inclination angle is changed from 15o to 90o. Smooth and rough surface of average roughness (0.02mm) are used and their effect on the heat transfer characteristics are s...

Our knowledge of the production of variant pneumococcus forms has been greatly clarified during the last few years by recognition of the fact that the species may be divided into at least two great groups including the so called S, or smooth forms, and the R, or rough forms. Although the terms rough and smooth have been derived essentially from the morphological characteristics of the colonies ...

Walls in discrete element method simulations of granular flows are sometimes modeled as a closely packed monolayer of fixed particles, resulting in a rough wall rather than a geometrically smooth wall. An implicit assumption is that the resulting rough wall differs from a smooth wall only locally at the particle scale. Here we test this assumption by considering the impact of the wall roughness...

Abstract: Turbulence intensity profiles are compared for smoothand rough-wall pipe flow measurements made in the Princeton Superpipe. The profile development in the transition from hydraulically smooth to fully rough flow displays a propagating sequence from the pipe wall towards the pipe axis. The scaling of turbulence intensity with Reynolds number shows that the smoothand rough-wall level de...

Texture is an important source of information for distinguishing surface properties. We are able to perceive various textural properties of surfaces from tactile or visual inputs. However, it is unclear how touch-produced sounds influence the various surface texture perceptions. In this study, we examined whether the touch sounds produced by different surface textures influence the various surf...

Laser surface patterning by Contact Particles Lens Arrays (CPLA) has been widely utilized for patterning of smooth surfaces but there is no technique developed by which CPLA can be deposited on a rough surface. For deposition of CPLA, conventional techniques require the surface to be flat, smooth and hydrophilic. In this study, a new method for the deposition of CPLA on a rough surface is propo...

A direct numerical simulation (DNS) of an unstably stratified convective boundary layer with system rotation was performed to study top-down and bottom-up diffusion processes. In order to better understand near-wall dynamics associated with scalar diffusion in the absence of surface roughness, direct simulation is utilized to numerically integrate the governing equations that model the atmosphe...

Flow reactors can be used to adjust the composition of aerosol particles if at least one of the components is volatile. Of course, the necessary thermodynamic boundary conditions in particular a defined vapour pressure level over the surface (or a part of the surface) have to be maintained along the reactor. In the case of water as one of the most important aerosol components this condition can...

Wall adsorption is a common problem in microfluidic devices, particularly when proteins are used. Here we show how superhydrophobic surfaces can be used to reduce protein adsorption and to promote desorption. Hydrophobic surfaces, both smooth and having high surface roughness of varying length scales (to generate superhydrophobicity), were incubated in protein solution. The samples were then ex...