Sökning: "Nonlinear flow"

Visar resultat 1 - 5 av 129 avhandlingar innehållade orden Nonlinear flow.

  1. 1. Acoustic characterization of orifices and perforated liners with flow and high-level acoustic excitation

    Författare :Lin Zhou; Hans Bodén; Wim De Roeck; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Bias Flow; Grazing Flow; Nonlinear Acoustics; Acoustic Impedance; Impedance Eduction; Single Mode Straightforward Method; Uncertainty Analysis; LEE; LNSE; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

    Sammanfattning : This thesis is motivated by the need for noise control in aircraft engine with orifices and perforated liner. The presence of high-level acoustic excitation, different flow situations either bias flow, grazing flow or any combination in the aircraft engine, makes the acoustic behavior complex due to the interaction between sound and flow over the lined wall. LÄS MER

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

    Författare :Carl-Erik Janson; Chalmers University of Technology; []
    Nyckelord :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. 3. Adjoint based control and optimization of aerodynamic flows

    Författare :Mattias Chevalier; KTH; []
    Nyckelord :transition control; flow control; nonlinear optimal control; boundary layer flow; Falkner-Skan-Cooke flow; quasi-1D flow; shape optimization; adjoint equations; DNS;

    Sammanfattning : .... LÄS MER

  4. 4. Nonlinear Identification and Control with Solar Energy Applications

    Författare :Linda Brus; Bengt Carlsson; Torbjörn Wigren; Graham C. Goodwin; Uppsala universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; feedforward control; model predictive control; nonlinear control; nonlinear systems; recursive identification; solar power; system identification; time delay systems; Automatic control; Reglerteknik; Automatic Control; Reglerteknik;

    Sammanfattning : Nonlinear systems occur in industrial processes, economical systems, biotechnology and in many other areas. The thesis treats methods for system identification and control of such nonlinear systems, and applies the proposed methods to a solar heating/cooling plant. LÄS MER

  5. 5. On Computational Homogenization of Flow in Porous Media

    Författare :Carl Sandström; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; multiscale; porous media; stokes flow; FE2; computational homogenization; darcy flow;

    Sammanfattning : Porous materials are present in many natural as well as engineered structures. Engineering examples of porous materials include sandstone in which oil can be stored, earth dams, composite materials, air filters and sanitary products with fiber networks (e.g. diapers). LÄS MER