[1] The carbon and oxygen isotopes of CO2 and the oxygen isotopes of H2O are powerful tracers for constraining the dynamics of carbon uptake and water flux on land. The role of land biota in the atmospheric budgets of these isotopes has been extensively explored through the lens of leaf-scale observations. At the ecosystem scale, kinetic fractionation is associated with molecular and turbulent ...

During the last three decades, the introduction of new construction materials (e.g. RCC (Roller Compacted Concrete), strengthened gabions) has increased the interest for stepped channels and spillways. However stepped chute hydraulics is not simple, because of different flow regimes and importantly because of very-strong interactions between entrained air and turbulence. In this study, new air-...

Understanding some of the basic wind engineering concepts helps one understand the chimney’s response. The circular cross section of the steel chimney characteristically provides aerodynamic lift perpendicular to the wind direction. Knowing how to predict and prevent these adverse responses is of critical importance to steel chimney design. I. STATIC WIND FORCES The force exerted by wind varies...

Draft is one of the most common complaints in the indoor environment. It may be caused by convective air currents along windows and other cold surfaces providing air movement in the occupied zone of heated spaces. The present paper comprises measurements of airflow characteristics (mean velocity, turbulence intenSity, energy spectra of the velocity fluctuations, etc.) in a wide range of spaces ...

Environmental turbulence is ubiquitous in natural habitats, but its effect on flying animals remains unknown because most flight studies are performed in still air or artificially smooth flow. Here we show that variability in external airflow limits maximum flight speed in wild orchid bees by causing severe instabilities. Bees flying in front of an outdoor, turbulent air jet become increasingly...

The influence of recycling on double-pass solar air collectors with welding of the V-corrugated absorber has been studied experimentally and theoretically. Welding the V-corrugated absorber and the recycle-effect concept to the solar air collector was proposed to strengthen the convective heat-transfer coefficient due to turbulence promotion. Both the recycle effect and the V-corrugated absorbe...

BACKGROUND AND PURPOSE Blood flow within the middle cerebral artery can be monitored by transcranial Doppler (TCD) ultrasonography. Arterial stenosis can produce turbulent flow, but controversy remains regarding the degree of stenosis needed to cause TCD-detectable turbulence. Furthermore, cerebral emboli and turbulent flow may coexist in the same patient. The current study was designed to stud...

An open question in warm rain process and precipitation formation is how rain forms in warm cumulus as rapidly as it has sometimes been observed. In general, the rapid growth of cloud droplets across the size gap from 10 to 50 μm in radius has not been fully explained. Three aspects related to the air turbulence and stochastic coalescence are considered here in an attempt to resolve this open q...

A coupled Lagrangian random walk and atmospheric turbulence model was employed to investigate the magnitude of isoprene source distribution within a mixed deciduous forest canopy undergoing defoliation. Modeled source distributions were studied to understand how the flux footprint evolved as the total amount and vertical distribution of foliage changed during the leaf senescing and abscission p...

In this research, a gas turbine blade cascade was investigated. Flow analysis around the blade was conducted using RSM and RNG.K-ε turbulence modeling and it is simulated by Fluent software. The results were considered for the cases as Mach number loss at the trailing edge of blade caused by vortexes that were generated at the end of blade. Effect of cooling flow through the trailing edge on th...