Sökning: "flow propagation velocity"

Visar resultat 1 - 5 av 35 avhandlingar innehållade orden flow propagation velocity.

  1. 1. Echocardiography/Doppler for the evaluation of coronary artery function, left ventricular function and the relationship between early diastolic and systolic function

    Författare :Reidar Winter; Malmö Institutionen för kliniska vetenskaper; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; coronary flow reserve; contrast echocardiography; early diastolic downward velocity; flow propagation velocity; colour M-mode; diastolic function; Echocardiography; Doppler; Kardiovaskulära systemet; Cardiovascular system;

    Sammanfattning : Two specific areas of development in echocardiography are assessment of left ventricular (LV) diastolic function and myocardial ischemia. This thesis describes echocardiographic methodology in these two areas. LÄS MER

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

    Författare :Lin Zhou; Hans Bodén; Wim De Roeck; KTH; []
    Nyckelord :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

  4. 3. Experimental Investigation of Velocity Gust in High Pressure Turbines

    Författare :Kai Freudenreich; KTH; []
    Nyckelord :turbomachinery; unsteady aerodynamics; gust; forcing function; forced response; transonic flow; annular cascade; Laser-Two-Focus Anemometer; experiments;

    Sammanfattning : This thesis investigates the unsteady three-dimensional gustfield in high subsonic and transonic turbine stages based onexperimental velocity data. The generation, propagation andinteraction mechanisms of the velocity gust in high pressureturbines are studied. LÄS MER

  5. 4. Rock grouting design: Rheological aspects and radial flow visualizations with ultrasound

    Författare :John Shamu; Stefan Larsson; Ulf Håkansson; Liangchao Zou; Chadi El Mohtar; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cement grouts; grouting; yield stress fluid YSF ; thixotropy; critical shear rate; radial flow; wall slip; Bingham model; Cementbaserade injekteringsmedels; injektering; icke-Newtonska vätskors; tixotropi; kritisk deformationshastigheten; radiella strömning; glidning; Bingham modell; Jord- och bergmekanik; Soil and Rock Mechanics;

    Sammanfattning : The rheological properties of cement-based grouts play a crucial role indetermining the final spread in grouted rock formations. In rheological terms,cement grouts are known to be complex time-dependent yield stress fluids,but their steady flow behavior is often described by the simple Binghamconstitutive law. LÄS MER

  7. 5. Vane applications and vane induced flow

    Författare :Fredrick Marelius; KTH; []
    Nyckelord :vane; erosion; shore protection; vortex; scour; ;

    Sammanfattning : Vanes are essentially small aspect ratio foils used forguiding sediment, by means of affecting the flow features. Theyare usually placed on the river bed and aligned with an angleof attack to the approach flow, thereby inducing a secondaryflow component that is used for guiding sediment in a desireddirection. LÄS MER