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  • A modeling study of katabatic flows

    Creator:
    Smith, Craig M.
    Abstract:
    A modeling study is undertaken to better understand the physics of katabatic flows. This study is divided into three topics; a comparison between a large eddy simulation (LES) and a mesoscale model of katabatic flows, a sensitivity study of katabatic flows to various physical parameters, and an investigation into the...
    Resource Type:
    Masters Thesis
    Full Text:
    ) and a mesoscale model of katabatic flows, a sensitivity study of katabatic flows to various physical

  • Discrete-time blade pitch control for wind turbine torque regulation with digitally simulated random turbulence excitation

    Creator:
    Sharif-Razi, Ali-Reza
    Abstract:
    A time domain simulation model which approximates the three-dimensional velocity fluctuations of wind turbulence has been developed. This model is used in a discrete time control algorithm to regulate the output torque of a wind turbine by changing the pitch angle of the turbine blade. The wind model provides a...
    Resource Type:
    Dissertation
    Full Text:
    velocity fluctuations of wind turbulence has been developed. This model is used in a discrete time

  • Turbulence induced loads on a teetered rotor

    Creator:
    Weber, Timothy L.
    Abstract:
    Development of variable speed horizontal axis wind turbines has resulted in a need for an analysis code with a rotor speed degree-of-freedom. This study develops a five degree-of-freedom time domain computer code that evaluates blade and rotor, mean and cyclic loads with nonlinear aerodynamics together with atmospheric turbulence as a...
    Resource Type:
    Dissertation
    Full Text:
    model is made by comparison of loads predictions between ESI-80 wind turbine data and analytical

  • A numerical study of the response of Lake Kinneret to wind forcing

    Creator:
    Vernieres, Guillaume
    Abstract:
    Lake Kinneret is Israel's only fresh water lake (unless you count the Dead Sea). It spans roughly 20km from north to south, and about 12km at its widest east west extent. It is not quite 50m deep at its deepest point. In late spring, the lake stratifies significantly and remains...
    Resource Type:
    Masters Thesis
    Full Text:
    centimeters for the surface layer. 74 4.17 Model prediction using a realistic uniform wind forcing

  • The use of conserved variables in the modeling and parameterization of shallow cumulus trade wind boundary layers

    Creator:
    Barbour, Philip L. (Philip Lee), 1960-
    Abstract:
    A time dependent model of the shallow, tropical convective boundary layer is developed and tested. To simplify the treatment of thermodynamic processes and return to first principles of physics, conserved quantities of entropy and total water density are used as primary model variables. In addition, a new shallow cumulus parameterization...
    Resource Type:
    Masters Thesis
    Full Text:
    . Abstract approved: A time dependent model of the shallow, tropical convective boundary layer is developed

  • Surface wind modification near mid-latitude ocean fronts : observational and dynamical analysis

    Creator:
    O'Neill, Larry W.
    Abstract:
    Interactions between surface winds and meanders in mid-latitude sea surface temperature (SST) fronts with horizontal length scales of 100-1000 km are investigated from satellite observations and numerical simulations. Observations from the Sea- Winds scatterometer on the QuikSCAT satellite show that the magnitude, direction, curl, and divergence of the surface wind...
    Resource Type:
    Dissertation
    Full Text:
    generated by small-scale SST gradients. In addition, a statistical coupled wind-SST response model is

  • Evaluation of horizontal axis wind turbine blade loads using unsteady aerodynamics

    Creator:
    Hartin, John R.
    Abstract:
    Most existing analyses of the blade loads on horizontal axis wind turbines are conducted using linear steady-state aerodynamics, but evaluation of loads resulting from wind turbulence or gusts may not be adequate using these techniques. This study develops single-parameter approximations for both the shed wake and trailing wake components of...
    Resource Type:
    Dissertation
    Full Text:
    Evaluation of horizontal axis wind turbine blade loads

  • A high power emulation of a wind farm

    Creator:
    Lalla, Chelsea
    Abstract:
    As more wind farms are connected to the grid, the variable nature of wind energy begins to influence grid stability. Energy storage could help smooth the variable nature of wind energy. Laboratory demonstration and exploration of the interaction between different energy storage devices and wind energy could help improve and...
    Resource Type:
    Masters Thesis
    Full Text:
    bromine battery, supercapacitors, hydropower, and wind energy. In this thesis, a scale model of the wind

  • Wind direction and effect of tree lean on coarse woody debris production

    Creator:
    Bustos-Letelier, Oscar
    Abstract:
    The natural fall of trees in riparian areas is an important source of coarse woody debris for mountain streams, improving fish habitat and influencing stream morphology. Existing models consider the probability of coarse woody debris entering a stream channel based upon trees having a random direction of fall without consideration...
    Resource Type:
    Masters Thesis

  • An empirical statistical model relating winds and ocean surface currents : implications for short-term current forecasts

    Creator:
    Zelenke, Brian Christopher
    Abstract:
    An empirical statistical model is developed that relates the non-tidal motion of the ocean surface currents off the Oregon coast to forecasts of the coastal winds. The empirical statistical model is then used to produce predictions of the surface currents that are evaluated for their agreement with measured currents. Measurements...
    Resource Type:
    Masters Thesis
    Full Text:
    wind forecasts were provided at 12 km resolution by the North American Mesoscale (NAM) model. First