Sökning: "Johan Revstedt"

Hittade 5 avhandlingar innehållade orden Johan Revstedt.

  1. 1. On the modelling of turbulent flow and mixing in stirred reactors

    Författare :Johan Revstedt; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; CFD; stirred reactors; impeller modelling; Energy research; mixing; LES; Energiforskning;

    Sammanfattning : This thesis concerns the numerical simulations and modelling of the flow structure and scalar transport in stirred reactors. For this Large Eddy Simulations (LES) have been used. The flow situation in a stirred reactor includes several flow phenomena that are not well predicted by "standard" two-equation models, e.g. LÄS MER

  3. 2. Effect of drag reducing plasma actuators using LES

    Författare :Romain Futrzynski; Gunilla Efraimsson; P. Henrik Alfredsson; Emma Alenius; Johan Revstedt; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; flow control; drag reduction; plasma actuator; DMD; LES; optimization; pulsating flow; strömningskontroll; motståndsminskning; plasmaaktuator; DMD; LES; optimering; pulserande strömning; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The work performed in this thesis explores new ways of reducing the drag of ground vehicles. Specifically, the effect of plasma actuators are investigated numerically with the intention to delay separation around a half-cylinder, a geometry chosen to represent a simplified A-pillar of a truck. LÄS MER

  4. 3. Lagrangian Particles in Turbulence and Complex Geometries

    Författare :Azad Noorani; Philipp Schlatter; Johan Revstedt; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct numerical simulation; wall turbulence; secondary motion; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : Wall-dominated turbulent dispersed multiphase flows occur in a variety of industrial, biological and environmental applications. The complex nature of the  arrier and the dispersed phase is elevated to a higher level introducing geometrical complexities such as curved walls. LÄS MER

  5. 4. The influence of inertia on the rotational dynamics of spheroidal particles suspended in shear flow

    Författare :Tomas Rosén; Fredrik Lundell; Minh Do-Quang; Johan Revstedt; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; dispersed particle flows; inertia; non-spherical particles; non-linear dynamics; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : Dispersed particle flows occur in many industrial, biological and geophysical applications. The knowledge of how these flow behave can for example lead to improved material processes, better predictions of vascular diseases or more accurate climate models. LÄS MER

  7. 5. Modelling of turbulent gas-particle flow

    Författare :Tobias Strömgren; Gustav Amberg; Arne Johansson; Johan Revstedt; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulent gas-particle flows; modelling; turbophoresis; two-way coupling; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : An Eulerian-Eulerian model for dilute gas-particle turbulent flows is developed for engineering applications. The aim is to understand the effect of particles on turbulent flows. The model is implemented in a finite element code which is used to perform numerical simulations. LÄS MER