Advanced search

Showing result 1 - 5 of 30 swedish dissertations matching the above criteria.

  2. 1. Low head pumped hydro storage with contra-rotating pump-turbines

    Author : Jonathan Fahlbeck; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy storage; Pumped hydro storage; CFD; Transients; Pump-turbine; Low head; OpenFOAM; Contra-rotating; Hydropower;

    Abstract : The increasing share of electrical energy production by intermittent sources pushes the demand for energy storage. Pumped hydro storage (PHS) has a long history of providing a cost-efficient energy storage solution. However, for PHS to be a viable option, a large head is typically required. READ MORE

  4. 2. CFD of Air Flow in Hydro Power Generators

    Author : Pirooz Moradnia; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; OpenFOAM; MultipleReferenceFrame; CFD; Generator; Launder-Sharma k-ε;

    Abstract : The air flow through a generator has been numerically investigated with different rotor and stator designs to give a better understanding of the flow for cooling purposes. A simple rotor design has been chosen to start with, and modified through a set of changes, where stepwisemodifications have been imposed to the design of the rotor and the stator. READ MORE

  5. 3. Flow over rough surfaces, and conjugate heat transfer, in engineering applications

    Author : Bercelay Niebles Atencio; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Naphthalene Sublimation Tecnhique; Antifouling paint; convective heat transfer; Roughness Function; correlation; CFD; RANS; stator channel; electric generator; Impinging Jet; Skin-Friction Drag; Rotating Disk; Ship Hull;

    Abstract : This thesis focuses on two important topics in the field of fluid mechanics and heat transfer that were treated separately. On the one hand, the flow over rough surfaces, which is not yet completely understood, despite of the fact that it has an important implication in many engineering applications, especially in the naval industry for ships and boats because the friction drag caused by fouling, antifouling coatings and roughness in general impacts the fuel consumption and toxic emissions to the atmosphere. READ MORE

  6. 4. Numerical and Experimental Investigations on Aerodynamic and Thermal Aspects of Rotating Wheels

    Author : Alexey Vdovin; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ventilation resistance; wind tunnel; brake cooling; ride height; aerodynamic moment; CFD; rim design; vehicle aerodynamics;

    Abstract : With todays and future environmental legislations for CO2 and other emission gases, all vehicle manufacturers are forced to further develop tools and methods to make their vehicles more energy efficient and environmentally friendly. One option to achieve this is to reduce the aerodynamic resistance since it has a significant influence on the vehicle fuel consumption, especially for velocities higher than 50 km/h. READ MORE

  7. 5. Towards Full Predictions of the Unsteady Incompressible Flow in Rotating Machines, Using OpenFOAM

    Author : Olivier Petit; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent Flow; Sliding Grid; Hydro Power; Kaplan Turbine; OpenFOAM; CFD;

    Abstract : The main objective of the present work is to validatemethodologies for accurate numerical predictions of the incompressible flow ofwater in the U9 Kaplan turbine model. The term “prediction” implies that the useof detailed experimental data for boundary conditions should be avoided, andthat all important features of the studied case should be included. READ MORE