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Turbulence and Reynolds number effects on the flow and fluid forces on a single cylinder in cross flow

The flow around a smooth and rigid tube (circular cylinder) in cross flow has been investigated experimentally. The experiments were carried out in a closed-circuit low-speed wind tunnel. Two test tubes (diameters 41 and 120 mm, respectively) fitted with end plates were used. The fluctuating pressures on the tube surface were sensed by microphones in pinhole arrangements while the modulus of the s

Free-stream turbulence and tube spacing effects on surface pressure fluctuations for two tubes in an in-line arrangement

An experimental investigation of surface pressure distributions (mean and r.m.s.) on two tubes (circular cylinders) mounted in an in-line or tandem arrangement was carried out in a low-speed, closed-circuit wind tunnel. The measurements were mainly performed at a subcritical Reynolds number, Re = 2·0 × 104, at three different turbulence intensities of the approaching cross-flow (0·1, 1·4 and 3·2%)

Numerical simulation of unsteady low-Reynolds number flow around rectangular cylinders

Calculations of unsteady two-dimensional-flow around rectangular cylinders at incidence are presented. The Reynolds numbers are low ( ⩽ 200), so that the flow presumably is laminar. The results are in reasonable agreement with the indeed scarce experimental data available at these low Reynolds numbers. An incompressible SIMPLEC code is used employing non-staggered grid arrangement. A third-order Q

Low-Reynolds number flow around a square cylinder at incidence: Study of blockage, onset of vortex shedding and outlet boundary condition

Calculations of unsteady 2D flow around a square cylinder at incidence (α=0°−45°) are presented. The Reynolds numbers are low (Re=45–200) so that the flow is presumably laminar. A von Kármán vortex sheet is predicted behind the cylinders with a periodicity which agrees well with experiments. An incompressible SIMPLEC code is used with a non-staggered grid arrangement. A third-order QUICK scheme is

Simulation of unsteady three-dimensional flow around a square cylinder at moderate Reynolds numbers

Direct numerical simulations of two-dimensional (2D) and 3-D unsteady flow around a square cylinder for moderate Reynolds numbers (Re=150–500) are performed, employing an implicit fractional step method finite-volume code with second-order accuracy in space and time. The simulations, which are carried out with a blockage ratio of 5.6%, indicate a transition from 2-D to 3-D shedding flow between Re

Large eddy simulation of flow past a square cylinder: Comparison of different subgrid scale models

Large eddy simulation of flow past a rigid prism of a square cross section with one side facing the oncoming flow at Re=2.2×104 is performed. An incompressible code is used employing an implicit fractional step method finite volume with second-order accuracy in space and time. Three different subgrid scale models: the Smagorinsky, the standard dynamic, and a dynamic one-equation model, are applied

Novel water penetration criterion for clay brick masonry claddings

Despite the impact of water penetration on the performance of building envelopes, no general agreement is available on implementing water penetration due to wind-driven rain (WDR) in hygrothermal and moisture safety analyses. This study proposes a novel criterion for water penetration in clay brick masonry that depends on the water content level of masonry. An experimental campaign investigating w

The Sweden Democrats and the Twitterstorm of the decade : from social media to riot through a rhetorical vision

Abstract in PolishW czasie europejskiego kryzysu migracyjnego prowokacyjna kampania reklamowa skrajnie prawicowej partii Szwedzkich Demokratów została zniszczona przez tłum. Od lat żadna inna kampania w Szwecji nie przyciągnęła podobnej uwagi i niechęci. To jakościowe studium przypadku przedstawia retorykę aktywizmu, która wywołała „Twitterową burzę dekady”. Poprzez analizę motywu fantazji określoAmidst the European migrant crisis, a provocative advertisement campaign by the far-right party the Sweden Democrats was destroyed by a mob. No other campaign in Sweden had attracted a similar amount of attention and resentment. This qualitative case study analyses the activism rhetoric that caused the ‘Twitterstorm’ of the decade. Through a fantasy theme analysis, it determines how the protesters

Individual differences in argument strength discrimination

Being able to discriminate poorly justified from well justified arguments is necessary for informed citizenship. However, it is not known whether the ability to recognize argument strength generalizes across different types of arguments, and what cognitive factors predict this ability or these abilities. Drawing on the theory of argument schemes, we examined arguments from consequence, analogy, sy

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The current debate on the Anthropocene is thus far dominated by the natural sciences. This leads to a simplistic analysis of environmental devastation and the underlying changes of human-nature relations. In this commentary, we urge the discipline of political science to enhance its engagement in the debate on the so-called human age and its far-reaching implications. The Anthropocene is character

Validation of cause of death classification after heart transplantation and cause-specific life expectancy compared to the general population

Background: Post heart-transplant survival has increased, but information is lacking on specific causes of death and life expectancy. We aimed to assess cause-specific loss of life-years compared to the general population, evaluate classification for cause of death after heart transplantation, and assess validity of cause of death data from the International Society of Heart and Lung Transplant (I

External electric field-dependent photoinduced charge transfer in non-fullerene organic solar cells

Based on Marcus theory, the photoinduced electron transfer properties of D-A type non-fullerene acceptor organic solar cells (OSCs) under the dependence of external electric field (Fext) were investigated. The research results shown that the charge transfer mode under different Fext intensities changes with certain regularity. Focusing on the important parameters (ΔG, λ, and VDA) that affect the c

Pupil dilation during negative prediction errors is related to brain choline concentration and depressive symptoms in adolescents

Depressive symptoms are associated with altered pupillary responses during learning and reward prediction as well as with changes in neurometabolite levels, including brain concentrations of choline, glutamate and gamma-aminobutyric acid (GABA). However, the full link between depressive symptoms, reward-learning-related pupillary responses and neurometabolites is yet to be established as these con

Controlling inventories in omni/multi-channel distribution systems with variable customer order-sizes

The fast growth of e-commerce and omni/multi-channel retailing brings new challenges for efficient inventory management. One such challenge concerns service differentiation across channels when upstream central warehouses satisfy both direct customer demand and replenishment orders from downstream retailers. Motivated by industry collaboration, we address this issue by developing a combined stock