Search for dissertations about: "Pär Jönsson"

Showing result 1 - 5 of 97 swedish dissertations containing the words Pär Jönsson.

  2. 1. Thermomechanical Processing of Nickel-Base Alloy 825

    Author : Munir Al-Saadi; Pär Jönsson; Christopher Hulme-Smith; Göran Engberg; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Alloy 825; Cast and wrought structures; Hot compression test; Microstructural evaluation; Modelling; Yield strength; Strengthening mechanisms; Materials Science and Engineering; Teknisk materialvetenskap;

    Abstract : Alloy 825 material was studied using a Gleeble-3800 thermosimulatorby performing single-hot compression experiments.Optical microscopy and electron backscatter diffraction wereutilized to characterize the microstructure. Dynamicrecrystallization is not considerable in the as-cast alloy anddislocation recovery is deemed to be dominant. READ MORE

  4. 2. Study of pyrolysis and gasification of biomass from the self-organization perspective

    Author : Aliaksandr Alevanau; Ersson Mikael; Weihong Yang; Pär Jönsson; Sylwester Kalisz; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; pyrolisys; pellets; hydrogen; gasification; Materials Science and Engineering; Teknisk materialvetenskap; Chemical Engineering; Kemiteknik;

    Abstract : This thesis focuses on the analysis of kinetics of i) low-temperature pyrolysis of gaseous hydrocarbons, ii) high-temperature steam gasification of char of wood pellets (>700oC), iii) high temperature pyrolysis of straw pellets in an atmosphere of argon and steam, and iv) high temperature pyrolysis of slices of transversally cut wooden sticks. The results of the kinetic measurements in the high-temperature cases are approximated using a least-square based optimization software, which was specially developed to analyse kinetics prone for deviation from the Arrhenius law. READ MORE

  5. 3. Coupling of a fundamental mathematical fluid flow model with computational thermodynamics model to study the decarburisation

    Author : Nils Å. I. Andersson; Pär Jönsson; Seppo Louhenkilpi; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : .... READ MORE

  6. 4. Numerical Study of the Gas Flow and Heat Transfer during Electromagnetic Stirring and Post Combustion in EAFs

    Author : Niloofar Arzpeyma; Pär Jönsson; Dongyuan Sheng; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; EMS; EAF; post combustion; heat transfer; duct system;

    Abstract : The effect of electromagnetic stirring on scrap melting and post combustion in two different electric arc furnaces (EAFs) have been studied using numerical modelling. The effect of electromagnetic stirring on melting of a piece of scrap located at the eccentric bottom tapping (EBT) region of an EAF has been studied. READ MORE

  7. 5. A Study of the Swirling Flow Pattern when Using TurboSwirl in the Casting Process

    Author : Haitong Bai; Mikael Ersson; Pär Jönsson; Yogeshwar Sahai; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flow pattern; swirling flow; TurboSwirl; CFD; turbulence models; water model; flödesmönster; roterandeflöde; TurboSwirl; CFD; turbulensmodeller; vattenmodell; Metallurgical process science; Metallurgisk processvetenskap;

    Abstract : The use of a swirling flow can provide a more uniform velocity distribution and a calmer filling condition according to previous studies of both ingot and continuous casting processes of steel. However, the existing swirling flow generation methods developed in last decades all have some limitations. READ MORE