Stagnant atmospheric conditions can lead to hazardous air quality by allowing ozone and particulate matter to accumulate and persist in the near-surface environment. By changing atmospheric circulation and precipitation patterns, global warming could alter the meteorological factors that regulate air stagnation frequency. We analyze the response of the National Climatic Data Center (NCDC) Air S...

We investigate the stability of steady planar stagnation flows of a dilute polyethylene oxide (PEO) solution using T-shaped microchannels. The precise flow rate control and well-defined geometries achievable with microfluidic fabrication technologies enable us to make detailed observations of the onset of elastically-driven flow asymmetries in steady flows with strong planar elongational charac...

the production of shear flow profile in a wind tunnel test-section with the aid of in-plain horizontal wire-grids is explained. the design procedure with experimental results are given. it is concluded that the deepest shear, produced by this procedure, cannot have a slope of more than 1.777. it is shown that the stagnation streamlines in a shear flow will be displaced due to the existence of s...