Search for dissertations about: "Convection flows"

Showing result 1 - 5 of 38 swedish dissertations containing the words Convection flows.

  2. 1. On optimization of natural convection flows

    Author : Clio Saglietti; Dan S. Henningson; Kurt Maute; KTH; []
    Keywords : Natural convection cooling; topology optimization; flow optimization; heat sink; conjugate heat transfer; differentially heated cavity; optimal initial disturbances; adjoint optimization;

    Abstract : Two different techniques are presented for enhancing the thermal  performance of natural convection cooled heat sinks. The physics is  described by solving the conjugate heat transfer problem with a  spectral element method. The temperature distribution is computed in  two sub-domains, whose solution is then conjugated. READ MORE

  4. 2. Convection in Loose-fill Attic Insulation

    Author : Paula Wahlgren; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; loose-fill insulation; forced convection; attics; natural convection; heat transfer; thermal insulation;

    Abstract : The objective of this study is to investigate the influence of convection on the thermal performance of loose-fill attic insulation under realistic climate conditions. In order to achieve this, a large-scale attic test model has been constructed in a climate chamber. READ MORE

  5. 3. Melt convection in welding and crystal growth

    Author : Minh Do-Quang; Gustav Amberg; Andreas Ludwig; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering physics; thermocapillary convection; gas-tungsten arc welding; floating zone; parallel computing; finite element method; Teknisk fysik; Engineering physics; Teknisk fysik;

    Abstract : A parallel finite element code with adaptive meshing was developed and used to study three dimensional, time-dependent fluid flows caused by thermocapillary convection as well as temperature and dopant distribution in fusion welding and floating zone crystal growth. A comprehensive numerical model of the three dimensional time-dependent fluid flows in a weld pool had been developed. READ MORE

  6. 4. Computational Modeling of Complex Flows

    Author : Johan Hoffman; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; computational fluid dynamics; adaptive finite element method; a posteriori error estimate; subgrid modeling; transition to turbulence; multiresolution analysis; object-oriented software; computational fluid dynamics;

    Abstract : In this thesis we consider the following aspects of computational modeling of complex flows: (i) subgrid modeling, (ii) stability, (iii) a posteriori error estimation, and (iv) computational platform. We develop a framework for adaptivity and error control for multiscale problems, in particular for turbulent flow, based on a posteriori error estimates. READ MORE

  7. 5. Distribution of Ventilation Air and Heat by Buoyancy Forces inside Buildings : An Experimental Study

    Author : Claes Blomqvist; Mats Sandberg; Per Heiselberg; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; building ventilation; thermal forces; buoyancy; gravity currents; large openings; heating; air quality; forced convection; free convection; Building engineering; Byggnadsteknik;

    Abstract : The main task of the ventilation system in a building is to maintain the air quality and (together with the heating or cooling system) the thermal climate at an acceptable level within the building. This means that a sufficient amount of ventilation air at the appropriate temperature and quality must be supplied to satisfy thermal comfort and air quality demands and that this air is distributed to the parts of the building where people reside. READ MORE