@phdthesis{Nowitzki2021, author = {Nowitzki, Mario}, title = {Development and validation of a gas-liquid two-phase model for industrial computational fluid dynamics applications}, doi = {10.26127/BTUOpen-5413}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-54130}, school = {BTU Cottbus - Senftenberg}, year = {2021}, abstract = {A local algebraic simulation model was developed, to determine the characteristic length scales for dispersed phases. This model includes the Ishii- Zuber drag model, the lift, the wall lubrication force and the turbulent dispersion force as well. It is based on the Algebraic Interface Area Density (AIAD) model from the Helmholtz Zentrum Dresden Rossendorf (HZDR), which provides the morphology detection and the free surface drag model. The developed model is in agreement with the current state of knowledge based on an examination of the theory and of state of science models for interface momentum transfer. This new simulation model was tested on three different experiments. Two experiments can be found in the literature, the Fabre 1987 and the Hewitt 1987 experiment. And the third simulation is based on a steam drum experiment. This steam drum experiment is designed with ERK Eckrohrkessel GmbH internals and was developed to examine the droplet mass flow out of the turbulent separation stage. The implementation of all models and tests was performed using Ansys CFX. The first analysis was carried out to reproduce a wavy stratified flow to examine the effects of different simulation model set-ups according to the velocity and kinetic energy profiles, as well as the pressure drop gradient and the water level measured by Fabre 1987. The second analysis was a proof on concept for reproducing the vertical flow pattern by an experiment from Hewitt 1987. The third simulation analysed the water distribution in the steam drum and feeding pipes system as well as the droplet carryover into the gas phase in the turbulent separation region of the drum. These simulations have shown, that the accuracy of the particle distribution model in interaction with the drag and non-drag forces is able to reproduce horizontal and vertical flow patterns. Higher deviations are recognised for the liquid volume fraction close above the interface. Generally, simulations can now be performed to optimise industrial steam drum designs.}, subject = {CFD; Grenzfl{\"a}che; Impuls{\"u}bertragung; Zweiphasenstr{\"o}mung; Numerische Str{\"o}mungssimulation; Two-phase flow; Particle interaction; Steam drum; Turbulence damping; Euler-Euler; Zweiphasenstr{\"o}mung; AIAD; E{\"o}tv{\"o}s Zahl; Partikelverteilung}, language = {en} }