Abstract It is observed that the feather surface exhibits anisotropic resistances for streamwise and spanwise flows. To obtain a qualitative understanding about effect of this resistance feature on boundary-layer transitional flow over flat plate, simple phenomenological model established in paper. By means large eddy simulation (LES) with high-order accurate finite difference method, numerical...

Smooth muscle cells and pericytes, together called mural cells, coordinate numerous vascular functions. Canonically, smooth muscle cells are ring-shaped and cover arterioles with circumferential processes, whereas pericytes extend thin processes that run longitudinally along capillaries. Nearly a century ago, Zimmerman described mural cells with mixed features of smooth muscle cells and pericyt...

Natural reservoirs are porous and permeable rocks containing deposits of hydrocarbons (oil reservoirs) or pure water (aquifers). Porosity and permeability are the most important physical properties of reservoirs that affect flow and transport. In general these geological parameters are stochastically modeled (see [?, ?] and references therein). As a consequence the equations governing flow and ...

The longitudinal dispersion coefficient is used to describe the change in characteristics of a solute cloud, as it travels along the longitudinal axis of a pipe. Taylor [1954] proposed a now classical expression to predict the longitudinal dispersion coefficient within turbulent pipe flow. However, experimental work has shown significant deviation from his prediction for Re < 20000. This paper ...

When fluid flows through a channel, pipe, or duct, there are two basic forms of motion: smooth laminar motion and complex turbulent motion. The discontinuous transition between these states is a fundamental problem that has been studied for more than 100 yr. What has received far less attention is the large-scale nature of the turbulent flows near transition once they are established. We have c...

The recent theoretical discovery of families of travelling wave solutions in pipe flow (Faisst & Eckhardt 2003; Wedin & Kerswell 2004; Hof et al. 2004) at Reynolds numbers lower than the transitional range naturally raises the question of their relevance to the turbulent transition process. Here a series of numerical experiments are conducted in which we look for the spatial signature of these ...

A physical model for flow characteristics analysis of labyrinth-channel emitter is reconstructed by Reverse Engineering from an injection molded part, and both laminar flow and turbulence models are adopted to simulate the flow state under the condition of low Reynolds numbers. According to the distribution of separation and reattachment points, the onset of transition from laminar to turbulent...