Sökning: "two phase flow"

Visar resultat 1 - 5 av 463 avhandlingar innehållade orden two phase flow.

1. 1. Experimental Heat Transfer, pressure drop, and Flow Visualization of R-134a in Vertical Mini/Micro Tubes

   Författare :Wahib Owhaib; Björn Palm; Tassos Karayiannis; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Minichannel; microchannel; heat transfer; pressure drop; single-phase; two-phase; flow boiling; flow visualization; dry out; bubble behavior; flow pattern.; Mechanical energy engineering; Mekanisk energiteknik;

   Sammanfattning : For the application of minichannel heat exchangers, it is necessary to have accurate design tools for predicting heat transfer and pressure drop. Until recently, this type of heat exchangers was not well studied, and in the scientific literature there were large discrepancies between results reported by different investigators. LÄS MER

3. 2. Adaptive Finite Element Methods for Compressible Two-Phase Flow

   Författare :Erik Burman; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; adaptive finite element methods; two-phase flow; compressible flow; conservation laws; hyperbolic systems; a posteriori error estimates; streamline diffusion; stability analysis; quantitative error control; adaptive algorithms; quantitative error control;

   Sammanfattning : In this thesis we develop, apply and analyse adaptive finite element methods with error control for compressible flow problems, focusing in particular on two-phase flow. The adaptive algorithms, aiming at quantitative error control with efficient use of computational resources, are based on a posteriori error estimates, where the error is estimated in terms of the computed solution, the local mesh-size and certain stability factors. LÄS MER

4. 3. Mass Conserving Simulations of Two Phase Flow

   Författare :Elin Olsson; Gunilla Kreiss; Stig Larsson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; free boundary; two phase flow; level set method; conservative; Numerical analysis; Numerisk analys;

   Sammanfattning : Consider a mixture of two immiscible, incompressible fluids e.g. oil and water. Since the fluids do not mix, an interface between the two fluids will form and move in time. LÄS MER

5. 4. Phase Doppler Anemometry in Unsteady Two-Phase Flow: A Novel Post-Processing Data Algorithm

   Författare :Tobias Bergenblock; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Circulating fluidized bed; Particle groups; Phase Doppler anemometry; Eulerian Lagrangian simulation; Particle flow measurements; Two-phase flow;

   Sammanfattning : This thesis presents a novel method to estimate particle fluctuations in unsteady two-phase flow using phase Doppler anemometry (PDA). A comprehensive derivation and asuccessful validation of a PDA data post-processing algorithm are given. LÄS MER

7. 5. A numerical study of two-fluid models for dispersed two-phase flow

   Författare :Reynir Levi Gudmundsson; Björn Sjögreen; Anders Petersson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Numerical analysis; two-phase flow; two-fluid mode; well-posedness; numerical experiments; Numerisk analys; Numerical analysis; Numerisk analys;

   Sammanfattning : In this thesis the two-fluid (Eulerian/Eulerian) formulation for dispersed two-phase flow is considered. Closure laws are needed for this type of models. We investigate both empirically based relations, which we refer to as a nongranular model, and relations obtained from kinetic theory of dense gases, which we refer to as a granular model. LÄS MER