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Hittade 4 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Numerical investigation of self-excited vibrations of a compressor cascade

    Författare :Moosa Muhammad; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flutter; turbomachinery; compressor blade; CFD; stability; aerodynamic damping; stability parameter; modeshape; Mechanical energy engineering; Mekanisk energiteknik;

    Sammanfattning : .... LÄS MER

  2. 2. Concepts for Power System Small Signal Stability Analysis and Feedback Control Design Considering Synchrophasor Measurements

    Författare :Yuwa Chompoobutrgool; Luigi Vanfretti; Mats Larsson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wide-area damping control; inter-area oscillations; power system stabilizers; PMU; Järnvägsgruppen - Elsystem; Järnvägsgruppen - Elsystem;

    Sammanfattning : In the Nordic power network, the existence of poorly damped low-frequency inter-area oscillations (LFIOs) has long affected stability constraints, and thereby, limited power transfer capacity. Adequate damping of inter-area modes is, thus, necessary to secure system operation and ensure system reliability while increasing power transfers. LÄS MER

  3. 3. Experimental study of fluid-structure interactions oon a generic model

    Författare :Davy Allegret-Bourdon; KTH; []
    Nyckelord :;

    Sammanfattning : A new type of test facility is presented which allows theinvestigation of fluid-structure interactions using a genericflexible model. Rather than modelling the complex geometry of aturbomachine blade passage or blade row, this test facilityuses a two dimensional generic bump located in a straightchannel in order to reach a better understanding of the bendingflutter phenomenon. LÄS MER

  4. 4. Flutter in sectored turbine vanes

    Författare :Olga V. Chernysheva; KTH; []
    Nyckelord :turbomachinery; aerodynamics; unsteady CFD; design; flutter;

    Sammanfattning : In order to eliminate or reduce vibration problems inturbomachines without a high increase in the complexity of thevibratory behavior, the adjacent airfoils around the wheel areoften mechanically connected together with lacing wires, tip orpart-span shrouds in a number of identical sectors. Although anaerodynamic stabilizing effect of tying airfoils together ingroups on the whole cascade is indicated by numerical andexperimental studies, for some operating conditions suchsectored vane cascade can still remain unstable. LÄS MER