Search for dissertations about: "physical flow"

Showing result 1 - 5 of 902 swedish dissertations containing the words physical flow.

2. 1. A Study of Using Pulsed Neutron Activation for Accurate Measurements of Water Flow in Pipes

   Author : Per Lindén; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; pulsed neutron activation; turbulent flow; neural networks; pipe flow; flow measurements; eddy diffusion; time averaging;

   Abstract : The objectives of this work were 1) to investigate the performance of the pulsed neutron activation (PNA) method for determination of mass flow of water in pipes, and 2) to improve the accuracy such that an error less than 1% become possible with the PNA method. The ultimate purpose is to develop this method into a high-accuracy portable and non-intrusive flow-meter that easily can be used as a calibration tool at a number of field applications, e. READ MORE

4. 2. Force Budget Analysis of Glacier Flow : Ice Dynamical Studies on Storglaciären, Sweden, and Ice Flow Investigations of Outlet Glaciers in Dronning Maud Land, Antarctica

   Author : Jim Hedfors; Veijo Pohjola; Else Kolstrup; Niels Reeh; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physical geography and sedimentology; force budget; ice flux; ice dynamics; mass balance; strain heating; climate change; Storglaciären; Dronning Maud Land; Antarctica; Naturgeografi och sedimentologi; Physical geography; Naturgeografi;

   Abstract : This thesis contributes to the understanding of glacier response to climate change by ice dynamical studies on Storglaciären, Sweden, and Bonnevie-Svendsenbreen, Kibergbreen and Plogbreen in Dronning Maud Land, Antarctica. Ice surface velocities, ice geometry and temperature information is fed through a force budget model to calculate ice mass outflux of these glacial systems via three-dimensional stress distributions for a flux-gate. READ MORE

5. 3. Modelling of Turbulent Flow and Heat Transfer for Building Ventilation

   Author : Peng Shia-Hui; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; large eddy simulation; turbulent buoyant convection; ventilation performance assessment; purging flow rate; SGS modelling; ventilation flow; stochastic Markov chain model; turbulence modelling; LRN k-w model; two-equation models; building ventilation; transfer probability; transition regime; modified SGS buoyancy model; energy backscatter;

   Abstract : This thesis contributes to studies on the assessment of building ventilation performance and the development of turbulence models accounting for Low-Reynolds-number (LRN) effects and buoyant convection with heat transfer. Assessments of building ventilation performance are discussed with respect to indoor air distribution and passive contaminant dispersion. READ MORE

6. 4. Ecosystem services of wetlands and wetlandscapes under hydro-climatic change : Impacts of water flow and inundation patterns

   Author : Imenne Åhlén; Jerker Jarsjö; Peter Hambäck; Georgia Destouni; Andrew Frampton; Heather E. Golden; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Hydrology; Ecohydrology; Wetlands; Wetlandscapes; Ecosystem services; Spatial Ecology; naturgeografi; Physical Geography;

   Abstract : Wetlands provide ecosystem services valuable for human society and are therefore often considered as nature based solution to different environmental problems. However, with centuries of wetland degradation due to anthropogenic pressures, such as agricultural expansion and forest industry, as well as pressures from climate change, there are large challenges for sustainable wetland management. READ MORE

7. 5. Flow of Colloidal Mesophases

   Author : S. Junaid S. Qazi; Adrian Rennie; Ritva Serimaa; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

   Abstract : This dissertation presents new work and results in the flow of complex fluids and experimental methodologies for their investigation. Plate-like colloidal particles of kaolinite and nickel hydroxide are studied. A study of lamellar fragments and their mixture with the nickel hydroxide particles is also presented. READ MORE