Sökning: "Coupled motions"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden Coupled motions.

  1. 1. Coupled vibrations in horizontal and vertical rotor-bearings systems

    Författare :Jean-Claude Luneno; Magnus Karlberg; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Technology - Engineering mechanics; Teknikvetenskap - Teknisk mekanik; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : For dynamical systems having several degrees of freedom, motion in one direction can induce motion in the other and/or vice versa. This means that there is a certain coupling between these two motions. Coupling can in some cases be a source of instability that causes self-excited vibrations in rotating machinery. LÄS MER

  3. 2. Cases of coupled vibrations and prametric instability in rotating machines

    Författare :Jean-Claude Luneno; Ilmar Santos; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : The principal task in this research project was to analyse the causes and consequences of coupled vibrations and parametric instability in hydropower rotors; where both horizontal and vertical machines are involved. Vibration is a well-known undesirable behavior of dynamical systems characterised by persistent periodic, quasi-periodic or chaotic motions. LÄS MER

  4. 3. Design and Control of Products Including Parts with Impacts

    Författare :Jenny Jerrelind; KTH; []
    Nyckelord :Nonlinear Dynamics; Impacts; Discontinuities; Subsystems; Chaos; Irregular Behaviour; Printer Dynamics; Suspensions; Coupled Systems; Control; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : Today's product development process should be rapid andcost-efficient, and should result in innovative and reliableproducts. A crucial factor is the dynamic behaviour of theproduct. LÄS MER

  5. 4. Strongly Coupled Performance Prediction for Sailing Yachts based on CFD

    Författare :Rickard Lindstrand Levin; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wind Triangle; RANS; Sailing; Velocity Prediction Program; Rigid Body Motion; Wide and Light Yacht; Laser dinghy;

    Sammanfattning : Quantifying performance of sailing yachts can be done in many different ways. Historically the most common way is a static approach where a steady state solution is obtained by solving equilibrium equations in 3 or 4 degrees of freedom. More recently, dynamic methods have appeared. In this thesis a method of the latter kind in proposed. LÄS MER

  7. 5. Quantum Wavepacket Dynamics in Molecular and Trapped Ion Systems

    Författare :Dong Wang; Tony Hansson; Volker Engel; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; wavepacket; revival; anisotropy; polarization; Molecular physics; Molekylfysik; kemisk fysik; Chemical Physics;

    Sammanfattning : The motions of a wavepacket in the two coupled potentials studied in this thesis can be classified into either bistable or astable motion according to the wavepacket interference at the curve crossing. Bistable motion, in which the wavepacket performs a coupled oscillation but remains in the same adiabatic and diabatic state, can exist both in bound-bound systems and bound-unbound ones with long time stability. LÄS MER