Sökning: "compressible"

Visar resultat 6 - 10 av 125 avhandlingar innehållade ordet compressible.

  1. 6. Flow Measuring Techniques in Steady and Pulsating Compressible Flows

    Författare :Fredrik Laurantzon; Henrik Alfredsson; Björn Lindgren; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flow measuring; compressible flow; steady flow; pulsating flow; hot-wire anemometry; cold-wire anemometry; Engineering mechanics; Teknisk mekanik;

    Sammanfattning : This thesis deals with flow measuring techniques applied on steady and pulsatingflows. Specifically, it is focused on gas flows where density changes canbe significant, i.e. compressible flows. LÄS MER

  3. 7. Acceleration of Compressible Flow Simulations with Edge using Implicit Time Stepping

    Författare :Evelyn Otero; Arthur Rizzi; Jesper Oppelstrup; Per Wahlund; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; compressible CFD; convergence acceleration; implicit time-stepping; matrix dissipation; line-implicit; performance optimization;

    Sammanfattning : Computational fluid dynamics (CFD) has become a significant tool routinely used in design and optimization in aerospace industry. Typical flows may be characterized by high-speed and compressible flow features and, in many cases, by massive flow separation and unsteadiness. LÄS MER

  4. 8. Acceleration of Compressible Flow Simulations with Edge Using  Implicit Time Stepping

    Författare :Evelyn Otero; Arthur Rizzi; Richard P. Dwight; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Compressible CFD; Convergence Acceleration; Implicit Time-Stepping; LU-SGS; Upwind Type Dissipation; Line-implicit; Ordering; Parallelization; Parameters; Multigrid;

    Sammanfattning : Computational fluid dynamics (CFD) is a significant tool routinely used indesign and optimization in aerospace industry. Often cases with unsteadyflows must be computed, and the long compute times of standard methods hasmotivated the present work on new implicit methods to replace the standardexplicit schemes. LÄS MER

  5. 9. 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

  7. 10. Shape optimization in compressible inviscid flow

    Författare :Oskar Enoksson; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis describes methods for aerodynamic optimization, including a new derivation of an adjoint method for efficient computation and regularization of the gradient. Also, a general method using different surface parameterizations is presented. LÄS MER