Coherent Structures in a Sharply Curved Bend with a Spur Dike at Different Configurations



Coherent structures in a sharply curved bend with and without a spur dike.
Köken, Mete; Budak, Ezgi (null; 2017-08-18)
: Results of three-dimensional (3D) Detached Eddy Simulation (DES) are used to investigate the changes in flow and large-scale coherent structures within a high-curvature open channel, with and without an isolated spur dike located on the outer bank of the
Coherent structures at different contraction ratios caused by two spill-through abutments
Köken, Mete (Informa UK Limited, 2017-8-23)
Detached eddy simulation (DES) at a channel Reynolds number of 45,000 is used to investigate the coherent structures forming around spill-through abutments located at opposite sides of a rectangular channel which contract the flow section. Changes in the coherent structures are investigated for two contraction ratios at two different scour stages. It is observed that at the small contraction ratio the coherent structures forming around the abutments are similar to the ones observed for isolated abutments. H...
Coherent structures around isolated spur dikes at various approach flow angles
Köken, Mete (2011-01-01)
The turbulent flow structures around an isolated spur dike located at three different approach flow angles are investigated. Detached eddy simulation is used at a channel Reynolds number of 45,000. Experimental velocity measurements were also conducted using acoustic Doppler velocimetry for validating the simulations. It is found that the size and orientation of the horseshoe vortex system change considerably with the approach flow angle. The main necklace vortex is largest in size and most coherent for 90 ...
Staggered grids discretization in three-dimensional Darcy convection
Karasözen, Bülent; Tsybulin, V. G. (2008-06-15)
We consider three-dimensional convection of an incompressible fluid saturated in a parallelepiped with a porous medium. A mimetic finite-difference scheme for the Darcy convection problem in the primitive variables is developed. It consists of staggered nonuniform grids with five types of nodes, differencing and averaging operators on a two-nodes stencil. The nonlinear terms are approximated using special schemes. Two problems with different boundary conditions are considered to study scenarios of instabili...
Coherent and convex measures of risk
Yıldırım, İrem; Körezlioğlu, Hayri; Department of Financial Mathematics (2005)
One of the financial risks an agent has to deal with is market risk. Market risk is caused by the uncertainty attached to asset values. There exit various measures trying to model market risk. The most widely accepted one is Value-at- Risk. However Value-at-Risk does not encourage portfolio diversification in general, whereas a consistent risk measure has to do so. In this work, risk measures satisfying these consistency conditions are examined within theoretical basis. Different types of coherent and conve...
Citation Formats
M. Köken and E. Budak, “Coherent Structures in a Sharply Curved Bend with a Spur Dike at Different Configurations,” 2018, Accessed: 00, 2021. [Online]. Available: