Sökning: "explicit Runge-Kutta"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden explicit Runge-Kutta.

1. 1. Runge-Kutta Solution of Initial Value Problems: Methods, Algorithms and Implementation

   Författare :Hans Olsson; Institutionen för datavetenskap; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computer science; stiffness; software; computational process; differential algebraic equations; ordinary differential equations; Runge-Kutta; initial value problems; time-stepping; system; kontroll; numerisk analys; Datalogi; control; numerical analysis; systems;

   Sammanfattning : The last decades have seen a strongly increasing use of computers for modeling larger and more complex systems. This has been made possible by a combination of increasing computer power and easy-to-use graphical modeling environments and libraries of components. LÄS MER

3. 2. Numerical Simulation of Turbulent Flows for Turbine Blade Heat Transfer Applications

   Författare :Jonas Larsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; k-.omega.; k-.epsilon.; explicit Runge-Kutta; finite volume; turbine; numerical method; non-linear; Navier-Stokes; supersonic; two-equation; external heat transfer; stagnation flow; two-dimensional; transition; low-Reynolds; turbulence model; impulse blade;

   Sammanfattning : Turbine blade heat transfer is an important engineering problem characterized by complex flow fields and high turbulence levels. This thesis is focused on using a full Navier-Stokes solver with two-equation eddy-viscosity models to predict external heat-transfer in single-stage, linear, two-dimensional uncooled turbine cascades. LÄS MER

4. 3. Adaptive Algorithms and High Order Stabilization for Finite Element Computation of Turbulent Compressible Flow

   Författare :Murtazo Nazarov; Johan Hoffman; Timothy J. Barth; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Compressible flow; adaptivity; finite element method; a posteriori error estimates; Implicit LES; Applied mathematics; Tillämpad matematik; Numerical analysis; Numerisk analys;

   Sammanfattning : This work develops finite element methods with high order stabilization, and robust and efficient adaptive algorithms for Large Eddy Simulation of turbulent compressible flows. The equations are approximated by continuous piecewise linear functions in space, and the time discretization is done in implicit/explicit fashion: the second order Crank-Nicholson method and third/fourth order explicit Runge-Kutta methods. LÄS MER

5. 4. Accuracy and Convergence Studies of the Numerical Solution of Compressible Flow Problems

   Författare :Erik Sterner; Per Lötstedt; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; computational fluid dynamics; Navier-Stokes equations; convergence acceleration; preconditioning; semi-implicit; multiblock; multigrid; finite volume method; Numerical Analysis; Numerisk analys;

   Sammanfattning : The numerical solution of compressible flow problems governed by the Navier-Stokes equations is considered. A finite volume method is used for the discretization in space. Different techniques to accelerate the convergence to a steady state are suggested, and the accuracy of the spatial difference operator is analyzed. LÄS MER

7. 5. Prediction of Wing Section Lift and Drag from Numerical Solutions of the Navier-Stokes Equations

   Författare :Björn Regnström; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; airfoil; incompresible flow; computational fluid dynamics; transition; numerical analysis; boundary layer stability;

   Sammanfattning : A Navier-Stokes finite difference method is developed and applied to two-dimensional, incompressible, viscous flow around wing sections at medium to high Reynolds numbers. An important feature of such flows is laminar boundary layers with spatially amplified Tollmien-Schlichting waves initiating transition to turbulence. LÄS MER