Separation of Enantiomers and Racemate Formation in Two-Dimensional Crystals at the Water Surface from Racemic α-Amino Acid Amphiphiles:  Design and Structure

Impact between a rigid flat plate and the free surface of water has been investigated experimentally and theoretically. Under two-dimensional conditions, the experiments give values of peak pressure of the same order as those recorded on ships slamming at sea, but very much smaller than would be expected from existing theories. New theoretical work is presented which takes account of the air trapped between the model and the water surface, and of both compressible and incompressible water movement. This shows good general agreement with the experiments, though further work is needed to confirm some of the assumptions made.

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A Study of Water Surface Deformation Due to Tip Vortices Wing-in-Ground Effect

Journal of Ship Research ◽

10.5957/jsr.2007.51.2.182 ◽

2007 ◽

Vol 51 (02) ◽

pp. 182-186

Author(s):

Tracie J. Barber

Keyword(s):

Water Surface ◽

Surface Deformation ◽

Three Dimensional ◽

Ground Effect ◽

Aerodynamic Performance ◽

The Body ◽

Vehicle Design ◽

Two Dimensional ◽

Tip Vortices ◽

Wing Tip

The accurate prediction of ground effect aerodynamics is an important aspect of wing-in-ground (WIG) effect vehicle design. When WIG vehicles operate over water, the deformation of the nonrigid surface beneath the body may affect the aerodynamic performance of the craft. The likely surface deformation has been considered from a theoretical and numerical position. Both two-dimensional and three-dimensional cases have been considered, and results show that any deformation occurring on the water surface is likely to be caused by the wing tip vortices rather than an increased pressure distribution beneath the wing.

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Two Dimensional Model for Backwater Geomorphology: Darby Creek, PA

Water ◽

10.3390/w11112204 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2204 ◽

Cited By ~ 3

Author(s):

Hosseiny ◽

Smith

Keyword(s):

Urban Areas ◽

Water Surface ◽

Integrated Model ◽

Shear Stresses ◽

Two Dimensional ◽

Morphological Alterations ◽

Digital Elevation ◽

Starting Point ◽

Spatio Temporal ◽

Elevation Model

Predicting morphological alterations in backwater zones has substantial merit as it potentially influences the life of millions of people by the change in flood dynamics and land topography. While there is no two-dimensional river model available for predicting morphological alterations in backwater zones, there is an absolute need for such models. This study presents an integrated iterative two-dimensional fluvial morphological model to quantify spatio-temporal fluvial morphological alterations in normal flow to backwater conditions. The integrated model works through the following steps iteratively to derive geomorphic change: (1) iRIC model is used to generate a 2D normal water surface; (2) a 1D water surface is developed for the backwater; (3) the normal and backwater surfaces are integrated; (4) an analytical 2D model is established to estimate shear stresses and morphological alterations in the normal, transitional, and backwater zones. The integrated model generates a new digital elevation model based on the estimated erosion and deposition. The resultant topography then serves as the starting point for the next iteration of flow, ultimately modeling geomorphic changes through time. This model was tested on Darby Creek in Metro-Philadelphia, one of the most flood-prone urban areas in the US and the largest freshwater marsh in Pennsylvania.

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