Numerical and experimental analysis of two-dimensional separated flows over a flexible sail

This paper is a numerical analysis of the flow over a exible sail with the usual two-dimensional model of ideal weightless incompressible fluid. The sail is assumed to be impervious, inelastic and weightless, and may or may not be mounted on a mast. Separated or attached flows are considered at any angle of attack. Our method is validated by numerical and experimental results, i.e. the sail shape and velocity field are determined by particle imaging velocimetry, and lift and drag by aerodynamic balance. Despite the simplicity of the wake model we use (the Helmholtz model), the computed free streamline geometry and especially the sail shape are in good agreement with the experimental and numerical data.

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Ideal fluid flow past obstacles in an arbitrary channel: comparison of numerical and experimental results

Journal of Fluid Mechanics ◽

10.1017/s0022112001005845 ◽

2001 ◽

Vol 447 ◽

pp. 129-148 ◽

Cited By ~ 2

Author(s):

R. WEBER ◽

J. HUREAU

Keyword(s):

Experimental Data ◽

Particle Image ◽

Numerical Data ◽

Two Dimensional ◽

Dimensional Model ◽

Image Velocimetry ◽

Two Dimensional Model ◽

Wake Model ◽

Weightless Fluid ◽

Good Agreement

This paper analyses a numerical model of a flow around an obstacle bounded in a channel with arbitrary walls. The model is based on the usual two-dimensional model of ideal incompressible weightless fluid. It is validated here by comparison with analytical findings and experimental data, which consisted of the velocity field determined by particle image velocimetry (PIV). Despite the simplicity of our wake model, the numerical data are usually in good agreement with the analytical and experimental data.

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Two-dimensional model for predicting performance of aerated grit chambersA paper submitted to the Journal of Environmental Engineering and Science.

Canadian Journal of Civil Engineering ◽

10.1139/l09-109 ◽

2009 ◽

Vol 36 (9) ◽

pp. 1567-1578 ◽

Cited By ~ 4

Author(s):

Alex Munoz ◽

Stephanie Young

Keyword(s):

Sensitivity Analysis ◽

Velocity Field ◽

Treatment Plant ◽

Poisson’S Equation ◽

Two Dimensional ◽

Dimensional Model ◽

Poisson's Equation ◽

Design Variables ◽

Predicting Performance ◽

Two Dimensional Model

A two-dimensional model was developed in this study. The model predicts the performance of a full-scale aerated grit chamber for grit removal from wastewater. The model numerically integrates Poisson’s equation, which describes the motion of the liquid induced by the rising air bubbles. The model makes use of finite element algorithms available in Mathcad to solve Poisson’s equation. The model was developed for predicting the velocity field in the chamber. The model was used to perform a sensitivity analysis of the design variables that affect the performance of an existing grit chamber at the Moose Jaw Wastewater Treatment Plant. The results of the sensitivity analysis indicate that predictions of velocity field are highly sensitive to energy transfer efficiency, air flowrate, and particle settling velocity but less sensitive to variations of wastewater flowrate, diffuser depth, and grid spacing.

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CHARGE-ORDERED CE-TYPE AND A-TYPE STATES IN HALF-DOPED MANGANITES

International Journal of Modern Physics B ◽

10.1142/s0217979202015005 ◽

2002 ◽

Vol 16 (32) ◽

pp. 4831-4837

Author(s):

ZHENGHUANG SHU ◽

J. M. DONG ◽

D. Y. XING

Keyword(s):

Coulomb Interaction ◽

Double Exchange ◽

Two Dimensional ◽

Dimensional Model ◽

Magnetic Structures ◽

Equal Footing ◽

Two Dimensional Model ◽

Doped Manganites ◽

Two Phases ◽

Good Agreement

According to the characteristics of the magnetic structures of the CE phase and the A phase for half-doped manganites, a two-dimensional model based on double exchange via degenerate eg orbitals as well as the Coulomb interaction and the superexchange interaction has been proposed to discuss the two phases on an equal footing. It is explained why the CE phase is usually easier to be realized for many half-doped manganites, while the A phase occasionally occurs. Moreover, our numerical calculations show that the two phases at x = 0.5 are not spin-canted, which is in good agreement with experimental observations.

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Commitment to pro- versus counter-attitudinal behavior and the dynamics of social representations

Swiss Journal of Psychology ◽

10.1024//1421-0185.61.1.34 ◽

2002 ◽

Vol 61 (1) ◽

pp. 34-44 ◽

Cited By ~ 8

Author(s):

Eric Tafani ◽

Lionel Souchet

Keyword(s):

Higher Education ◽

Social Representations ◽

Cognitive Restructuring ◽

Social Representation ◽

Two Dimensional ◽

Dimensional Model ◽

Social Actions ◽

The Social ◽

Two Dimensional Model ◽

Students Attitudes

This research uses the counter-attitudinal essay paradigm ( Janis & King, 1954 ) to test the effects of social actions on social representations. Thus, students wrote either a pro- or a counter-attitudinal essay on Higher Education. Three forms of counter-attitudinal essays were manipulated countering respectively a) students’ attitudes towards higher education; b) peripheral beliefs or c) central beliefs associated with this representation object. After writing the essay, students expressed their attitudes towards higher education and evaluated different beliefs associated with it. The structural status of these beliefs was also assessed by a “calling into question” test ( Flament, 1994a ). Results show that behavior challenging either an attitude or peripheral beliefs induces a rationalization process, giving rise to minor modifications of the representational field. These modifications are only on the social evaluative dimension of the social representation. On the other hand, when the behavior challenges central beliefs, the same rationalization process induces a cognitive restructuring of the representational field, i.e., a structural change in the representation. These results and their implications for the experimental study of representational dynamics are discussed with regard to the two-dimensional model of social representations ( Moliner, 1994 ) and rationalization theory ( Beauvois & Joule, 1996 ).

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