Search for dissertations about: "operational modal analysis"

Showing result 1 - 5 of 13 swedish dissertations containing the words operational modal analysis.

2. 1. Nonaxisymmetric experimental modal analysis and control of resistive wall MHD in RFPs : System identification and feedback control for the reversed-field pinch

   Author : K Erik J Olofsson; Per Brunsell; Marco Ariola; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magnetic confinement fusion; Reversed-field pinch; System identification; Magnetohydrodynamics; Modal analysis; Automatic control; Resistive wall modes;

   Abstract : The reversed-field pinch (RFP) is a device for magnetic confinement of fusion plasmas. The main objective of fusion plasma research is to realise cost-effective thermonuclear fusion power plants. The RFP is highly unstable as can be explained by the theory of magnetohydrodynamics (MHD). READ MORE

4. 2. Sound generation in metal flue organ pipes: On the influence of asymmetric flue exit geometry and vibrations of the upper labium with particular emphasis on the early response

   Author : Matthias Scholz; Chalmers tekniska högskola; []
   Keywords : jet contraction; wall vibrations; CFD; jet velocity profile; tap tone; asymmetry of flue exits; operational deflection shapes; Coanda effect; yielding upper labium; modal analysis; bottom clamped cylinder; vibration measurements; metal flue organ pipes; dipole; initial jet formation;

   Abstract : Sound generation in flue organ pipes is caused by the non-linear interaction between an instable jet and a tube resonator. Our understanding of this very complex physical process is still incomplete, and there is not yet a model that can explain all details of the richness in pipe sound which can be achieved by a trained organ pipe voicer. READ MORE

5. 3. Modelling and simulation of electromagnetic audible noise generated by traction motors

   Author : Fredrik Botling; Ines Lopez Arteaga; Siv Leth; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vibro-acoustics; Electromagnetic noise; traction motor; modal analysis; multi-physics; Vehicle and Maritime Engineering; Farkostteknik;

   Abstract : An annoying tonal noise is produced by modern electrical trains duringacceleration and deceleration. This noise is caused by electromagneticforces generating structural vibrations, especially from the traction motors. READ MORE

6. 4. Regional Intermodal Transport Systems : Analysis and Case Study in the Stockholm-Mälaren Region

   Author : Behzad Kordnejad; Bo-Lennart Nelldal; Rickard Bergqvist; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Järnvägsgruppen - Effektiva tågsystem för godstrafik; Järnvägsgruppen - Effektiva tågsystem för godstrafik;

   Abstract : The global trend of urbanization is evident and also valid in Sweden and for the Stockholm-Mälaren region, also referred to as the Mälaren valley, a region consisting of metropolitan Stockholm and areas around the lake of Mälaren. In this context, efficient urban freight transportation has emerged as essential for sustainable development of urban areas. READ MORE

7. 5. Predicting Xenon Oscillations in PWRs using Intrusive Reduced Order Modelling

   Author : Kristoffer Pedersen; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Reduced Order Modeling; Modal Decomposition; Multi-Group Diffusion Theory; Xenon Oscillations;

   Abstract : The increasing presence of intermittent energy sources in the Swedish electricity grid necessitates a transition of Swedish nuclear reactors from constant base load operation to load-following mode. However, such changes in power can induce xenon oscillations, a phenomenon that poses operational challenges and the risk of fuel damage. READ MORE