Sökning: "Nonlinear damping"

Visar resultat 1 - 5 av 44 avhandlingar innehållade orden Nonlinear damping.

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. Multi Quanta Relaxation and Nonclassicality of Nonlinear Oscillators

   Författare :Aurora Voje; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nonlinear Damping; Nonclassical States; Entanglement; Quantum Duffing Oscillator;

   Sammanfattning : The focus of the study is the free quantum evolution of Duffing oscillators which are nonlinearly coupled to bosonic environments. The work evolves from a particular system of an undamped, nonlinear graphene resonator mode to a more generalized framework of oscillator modes interacting with two different configurations of bosonic environments. LÄS MER

4. 3. Nonlinear dynamic analysis of vertical rotors with tilting pad journal bearings

   Författare :Gudeta Benti; Jan-Olov Aidanpää; Rolf Gustavsson; Roland Larsson; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vertical rotor; tilting pad journal bearing; stiffness; damping; Machine Design; Maskinkonstruktion;

   Sammanfattning : .... LÄS MER

5. 4. Eigenfrequency Analysis FE-Adaptivity and a Nonlinear Eigenproblem Algorithm

   Författare :Patrik Hager; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear eigenvalue; finite element; adaptivity; superconvergent patch recovery; rational krylov;

   Sammanfattning : Engineering often pose the problem of computing the frequencies with which a system oscillates and the corresponding displacement patterns the system forms, and in case damping is present then the rates of which the amplitudes of the displacement patterns decay are also required. It is necessary to compute these quantities within a prescribed accuracy and the effort required for the computations should be minimised. LÄS MER

7. 5. Characterisation of Nonlinear Structural Dynamic Systems in Conceptual Design

   Författare :Niclas S Andersson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Structural dynamics; Model order reduction; Nonlinear characterisation; Multi-body dynamics; Frequency response functions; Multisines; Response classification; Driveline systems; Concept design analysis; Stepped-sine; Support vector machine;

   Sammanfattning : The engine and driveline systems of passenger cars generates and distributes the necessary driving power and are major contributors to vehicle emissions, noise and vibrations, etc. More environmental friendly technologies under development are expected to intensify and add new comfort related problems, since most of them affect vibration sources or system damping. LÄS MER