Search for dissertations about: "tracer gas measurements"

Showing result 1 - 5 of 31 swedish dissertations containing the words tracer gas measurements.

  1. 1. Alternative methods for analysing moisture transport in buildings : Utilisation of tracer gas and natural stable isotopes

    Author : Kjartan Gudmundsson; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tracer gas; water vapour permeability; diffusion; surface diffusion; isotopic analysis; deuterium; oxygen-18; fractionation; vapour barrier; transient numerical modelling of diffusion; Building engineering; Byggnadsteknik;

    Abstract : New methods, based on tracer gas measurements and isotopicanalysis can be used to evaluate the moisture properties ofbuilding materials and provide the means for forensic analysisof the origins and history of excessive water in buildings, theimmediate practical consequences of which will be the abilityto improve the moisture performance of constructions. It is shown, in theory and through measurements how thewater vapour permeability of porous building materials can witha good degree of accuracy be estimated with tracer gasmeasurements that provide an efficient alternative to the cupmethod. READ MORE

  2. 2. Gas Mixing in a Circulating Fluidised Bed Boiler

    Author : Johan Sternéus; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; circulating fluidized bed; gas mixing; tracer; boiler; dispersion; scaling; turbulence; two-phase flow; fluidization;

    Abstract : The present thesis is a study on the gas-mixing behaviour in a circulating fluidised bed (CFB) boiler. The aim is to describe how gas is spread in different regions of a CFB furnace and to explain variations in the mixing rate under different operating conditions. READ MORE

  3. 3. Natural Ventilation and Air Infiltration in Large Single‑Zone Buildings : Measurements and Modelling with Reference to Historical Churches

    Author : Abolfazl Hayati; Magnus Mattsson; Mats Sandberg; Jens Fransson; Guilherme Carrilho da Graça; Högskolan i Gävle; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Natural ventilation; Airing; Air infiltration; Single-sided ventilation; Cross flow; Large single zones; Historical Churches; Model evaluation optimization; Field measurements; Wind tunnel; Indoor climate and Energy simulation; IDA-ICE; Tracer gas technique; Pressurization test.; Naturlig ventilation; Vädring; Luftinfiltration; Ensidig ventilation; Tvärdrag; Höga en-zonsbyggnader; Kulturhistoriska kyrkor; Modellutvärdering optimering; Fältmätningar; Vindtunnel; Inomhusklimat och energisimulering; IDA-ICE; Spårgas teknik; Trycksättningstest.; Hållbar stadsutveckling; Sustainable Urban Development;

    Abstract : Natural ventilation is the dominating ventilation process in ancient buildings like churches, and also in most domestic buildings in Sweden and in the rest of the world. These buildings are naturally ventilated via air infiltration and airing. READ MORE

  4. 4. Calibration and quality assessment of DESCARTES : grabsampler for stratospheric tracers

    Author : Johan Arvelius; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Adsorption; Balloon; Carboxen; CFC; Chloro-Fluoro Carbon; Grab sampling; Halocarbon; Molecular sieve; Stratospheric tracer; Tracer; Adsorption; Ballong; Carboxen; CFC; Halogeniserade kolväten; Klor-Flourkarbon; Spårgas; Stratosfärisk spårgas; Space physics; Rymdfysik;

    Abstract : DESCARTES is a light-weight, balloon-borne grab sampler for stratospheric long-lived tracers developed at the University of Cambridge. 33 flights have been performed with two versions of the instrument at northern latitudes by the DESCARTES team at the Swedish Institute of Space Physics (IRF) in Kiruna during the years 1997-2000. READ MORE

  5. 5. Experimental investigation of flows related to gas turbine combustion

    Author : Dragan Stankovic; Strömningsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical engineering; combusiton; flameless; jets in cross flow; chemiluminescence; POD; LIF; PIV; Spray; Gas Turbine; single digit NOx; Premixed Combustion; hydraulics; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Abstract : The notion of "global warming" has become a major public-domain concept as an environmental threat to our future on earth. Independently of the accuracy of existing prediction of combustion emissions on the climate on earth, the concept of reducing combustion emissions has been an important political driving force in imposing more and more severe restrictions on harmful emissions from combustion. READ MORE