Sökning: "free-surface flow"

Visar resultat 1 - 5 av 50 avhandlingar innehållade orden free-surface flow.

1. 1. Potential Flow Panel Methods for the Calculation of Free-surface Flows with Lift

   Författare :Carl-Erik Janson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; desingularized; shape optimization; Rankine source; waves; OCTOPUS; dipole; MMA; Dawson operator; boundary layer; vortex; Method of Moving Asymptotes; nonlinear; sailing yacht; four point operator; surface piercing wing; Navier-Stokes; numerical method; lift force; raised panel method; discrete Fourier transform; collocation point shift; potential flow; CFD; free surface; induced drag; SHIPFLOW; dispersion; damping; analytical method; hydrofoil;

   Sammanfattning : Two non-linear Rankine-source panel methods are developed and implemented in the same computer code. The first method uses a four-point upwind operator on the free-surface to compute the velocity derivatives and to enforce the radiation condition while the second method uses an analytical expression for the velocity derivatives and a collocation point shift one panel upstream to prevent upstream waves. LÄS MER

3. 2. Stability of the free-surface problem arising in ice-sheet- and glacier modeling : Numerical investigation and stabilization

   Författare :André Löfgren; Josefin Ahlkrona; Fabien Gillet-Chaulet; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ice-sheet modeling; glacier modeling; ice-sheet dynamics; free-surface flow; stability; stabilization; free-surface stabilization algorithm; Numerical Analysis; numerisk analys;

   Sammanfattning : This thesis consists of two papers dealing with a stabilization method for free-surface flows. The method was initially developed to stabilize mantle-convection simulations, but is in this work extended to ice-sheet- and glacier modeling. LÄS MER

4. 3. Conduction laser welding : modelling of melt pool with free surface deformation

   Författare :Josefine Svenungsson; Högskolan Väst; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Conduction laser welding; numerical modelling; Computational Fluid Dynamics; OpenFOAM; free surface deformation; melt pool; Production Technology; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik;

   Sammanfattning : Laser welding is commonly used in the automotive-, steel- and aerospace industry. It is a highly non-linear and coupled process where the weld geometry is strongly affected by the flow pattern in the melt pool. Experimental observations are challenging since the melt pool and melt flow below the surface are not yet accessible during welding. LÄS MER

5. 4. Simulations and measurements of free surface flow in regulated rivers

   Författare :Anders G. Andersson; Mats Billstein; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

   Sammanfattning : Open channel flow near hydropower stations is of interest for both engineering and environmental applications. In this research project Computational Fluid Dynamics simulations of free surface flow in regulated rivers were applied with both fish migration and validation of numerical simulations in focus. LÄS MER

7. 5. Fully Nonlinear Unsteady Three-Dimensional Boundary Element Method for Ship Motions in Waves

   Författare :Martin Kjellberg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; BEM; potential flow; MEL; ship motions; free surface; wave resistance; fully nonlinear; time-dependent;

   Sammanfattning : The prediction of the behavior of ships in a seaway has been an important topic in ship design since the beginning of modern naval architecture. In recent years, computer simulations using numerical methods based on mathematical models of the ship hydrodynamics problem has become a valuable tool for researchers and engineers working in this field. LÄS MER