Sökning: "fluctuating boundary"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden fluctuating boundary.

1. 1. Power Reactor Noise Studies and Applications

   Författare :Vasiliy Arzhanov; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; power spectra; control rod vibrations; Green s function; nesting hypothesis; adjoint function; fluctuating boundary; noise diagnostics; Accelerator Driven System; localisation algorithm; point reactor and adiabatic approximation;

   Sammanfattning : The present thesis deals with the neutron noise arising in power reactor systems. Generally, it can be divided into two major parts: first, neutron noise diagnostics, or more specifically, novel methods and algorithms to monitor nuclear industrial reactors; and second, contributions to neutron noise theory as applied to power reactor systems. LÄS MER

3. 2. Turbulence Measurements in a Natural Convection Boundary Layer and a Swirling Jet

   Författare :Abolfazl Shiri; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; swirl; constant current bridge; high Rayleigh number; natural convection; Jet; cold-wire thermometry; vertical cylinder; laser Doppler anemometry; turbulent boundary layers;

   Sammanfattning : Two sets of experimental measurement were carried out on an axisymmetric swirling jet flow and a natural convection boundary layer. In the first experiment, the far field of an incompressible swirling jet, discharged into a quiescent ambient has been studied using laser Doppler anemometry. LÄS MER

4. 3. Numerical Computations of Wakes Behind Wind Farms : A tool to study Farm to Farm interaction

   Författare :Ola Eriksson; Stefan Ivanell; Anna Rutgersson; Simon-Philippe Breton; Philippe Chatelain; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Wind turbine; Wind power; Wind farm; Wakes; Long distance wakes; Farm-Farm; Farm to farm interaction; Wind farm cluster; Large Eddy simulations; LES; Actuator disc method; ACD; CFD; Ellipsys3D; Prescribed boundary layer; PBL; Forced boundary layer; FBL; Meteorologi; Meteorology;

   Sammanfattning : More and larger wind farms are planned offshore. As the most suitable sites to build are limited these new wind farms will be constructed near to each other in so called wind farm clusters. Behind the wind turbines in these farms there is a disrupted flow of air called a wake that is characterized by reduced wind speed and increased turbulence. LÄS MER

5. 4. Numerical and Experimental study of shock boundary layer interaction in unsteady transonic flow

   Författare :Olivier Bron; KTH; []
   Nyckelord :Shock Boundary Layer Interaction; Shock Motion; Unsteady Flows; Nozzle Flows; Potential Interaction; Back Pressure Perturbations;

   Sammanfattning : A prerequisite for aeroelastic stability prediction inturbomachines is the understanding of the fluctuatingaerodynamic forces acting on the blades. Unsteady transonicflows are complex because of mutual interactions betweentravelling pressure waves, outlet disturbances, shock motion,and fluctuating turbulent boundary layers. LÄS MER

7. 5. Experimental studies in jet flows and zero pressure-gradient turbulent boundary layers

   Författare :Ramis Örlü; P. Henrik Alfredsson; Tim B. Nickels; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Axisymmetric jet; swirling jet; coaxial jet; heated jet; zero pressuregradient turbulent boundary layer; wall-bounded turbulent flows; overlap region; passive scalar mixing; hot-wire anemometry; spatial resolution.; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : This thesis deals with the description and development of two classical turbulent shear flows, namely free jet and flat plate turbulent boundary layer flows. In both cases new experimental data has been obtained and in the latter case comparisons are also made with data obtained from data bases, both of experimental and numerical origin. LÄS MER