Search for dissertations about: "numerical model"

Showing result 21 - 25 of 1982 swedish dissertations containing the words numerical model.

  2. 21. Numerical Investigations of Turbulent Flow in Water Turbines

    Author : Håkan Nilsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multiblock; Parallel; Visualization; Validation; Verification; Turbine; CFD; Francis; Numerical; Kaplan;

    Abstract : This thesis investigates turbulent flow in water turbines, focusing onthe flow in the vicinity of reaction water turbine runners such as theKaplan runner and the Francis runner. The method of investigationis principally numerical although some experimental observations andmeasurements made in the present work and elsewhere are included. READ MORE

  4. 22. Efficiency factors for space heating system in buildings

    Author : Christian Brembilla; Thomas Olofsson; Ronny Östin; Mohsen Soleimani-Mohseni; Bjørn Reidar Sørensen; Umeå universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Efficiency factors of space heating; hydronic panel radiator; hydronic floor heating; multilayer wall; numerical modelling; room control volume; decrement factor; time delay; heat conduction; heat convection; heat radiation; heat storage; thermal inertia; Euler solver; Newton-Raphson method; synthetic weather file; feedback and feed-forward control strategies; adaptive control; validation methodology; uncertainty bands; robustness of model predictions; thermostatic booth simulator; differential sensitivity analysis; transient model of panel radiator with multiple storage elements; active thermal mass; benchmark performance indicator; linear regression model; calibration through uncertainty bands; hybrid model of low-energy building: law driven data driven; outdoor temperature compensation heating curve; solar radiation model; finite difference method; heat equation;

    Abstract : The thesis focuses on the efficiency of the space heating system. In particular, the efficiency factors measure the efficiency of thermal zone. The efficiency factors measures how the energy is used in a space heating. READ MORE

  5. 23. Numerical modelling of geomaterials at failure

    Author : Alex Spetz; Byggnadsmekanik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; soil-structure interaction; soil plasticity; phase-field fracture model; compression driven fractures; artificial rock; porous rock; finite element analysis; isogeometric analysis; NURBS; numerical methods;

    Abstract : Geotechnical engineering is the science dealing with mechanics of soils and rocks and its engineering applications. Geotechnical engineering projects vary in a wide range, from evaluation of the stability of natural slopes and man-made soil deposits, to the design of earthworks and foundations. READ MORE

  6. 24. Terrain Modelling with GIS for Tectonic Geomorphology : Numerical Methods and Applications

    Author : Gyözö Jordan; Ulf Qvarfort; Tsehaie Woldai; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Environmental technology; digital elevation model; digital terrain modelling; GIS; morphometry; tectonic geomorphology; Miljöteknik; Environmental engineering; Miljöteknik;

    Abstract : Analysis of digital elevation models (DEMs) by means of geomorphometry provides means of recognising fractures and characterising the morphotectonics of an area in a quantitative way. The objective of the thesis is to develop numerical methods and a consistent GIS methodology for tectonic geomorphology and apply it to test sites. READ MORE

  7. 25. A Realizable Hybrid Mixture-Bubble Model for Cavitating Flows

    Author : Ebrahim Ghahramani; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multi-scale model; Homogeneous mixture model; Cavitation; Disperse multiphase flow; Eulerian-Lagrangian model; OpenFOAM;

    Abstract : Cavitating multi-phase flows include an extensive range of cavity structures with different length scales, from micro bubbles to large sheet cavities that may fully cover the surface of a device. To avoid high computational expenses, incompressible transport equation models are considered a practical option for simulation of large scale cavitating flows, normally with limited representation of the small scale vapour structures. READ MORE