{"id":{"repo_id":"tu-berlin","oai_identifier":"oai:depositonce.tu-berlin.de:11303/21057"},"canonical_url":"https://search.dev.ndltd.org/etd/tu-berlin/oai:depositonce.tu-berlin.de:11303/21057","repository":{"repo_id":"tu-berlin","name":"Technische Universität Berlin","base_url":"https://api-depositonce.tu-berlin.de/server/oai/request"},"display":{"title":"Extension and further validation of a 3D two-phase flow model for flow, transport and mass transfer in sewer systems","abstract":"Sewer networks are integral infrastructures in a well-planned city. Their vital role lies in efficiently transporting both wastewater to treatment facilities and rainwater from residential areas. The emission of hydrogen sulphide (H2S) combined with the oxygen (O2) present in the system can pose a significant threat to the integrity of concrete channels which is amplified for older sewer systems. Not only can its release lead to the erosion of sewer walls due to concrete corrosion, but it also presents a safety hazard for those working in the sewer environment. Not to mention the accompanying high costs for maintenance to mitigate these problems. The generation of hydrogen sulphide and the concentration of oxygen in sewers are influenced by various factors, including turbulent flow conditions, hydraulic retention time, flow velocities, and pH value. Numerical modeling with Computational Fluid Dynamics (CFD) software provides a valuable tool for studying multiphase flows and understanding the complex interactions between fluid dynamics and chemical processes. This doctoral thesis focuses firstly on validating the air phase flow in the sewer headspace. The solver for simulating mass transfer of H2S developed by Teuber (2020) in the OpenFOAM framework is further validated and then extended and validated to account for O2. Simulations of the high-resolution models were carried out on a high-performance computing cluster. Chapter 1 of this thesis deal with the general introduction to the problems of odour and corrosion in sewer systems, while chapter 2 provides a concise summary of the model's principles and tools used, along with the developed solver extensions. In Chapter 3 the updated and extended solvers, interH2SFoam and interO2Foam respectively, are validated using a quasi-steady state tank. These solvers accurately reproduced concentration profiles and equilibrium concentrations based on Henry's law, including the temperature-dependent behaviour of the Henry coefficient. In Chapter 4, the volume-of-fluid (VOF) approach implemented in OpenFOAM was applied to analyze two-phase flow hydraulics in a lab-scale rectangular duct. The interH2SFoam solver was further validated for turbulent conditions later in the chapter, with results compared to the results of Teuber et al. (2019b) showing good agreement. To validate the capability of the interO2Foam solver for gas transport in sewer headspace, experimental data from Bentzen et al. (2016) was used. Simulated results were compared to experimental data and a 1D analytical solution for transport, yielding acceptable agreement. In Chapter 5, the interO2Foam solver was validated using the field study of Madsen et al. (2006). The interFoam solver achieved a hydraulically steady state and was validated against analytical data. After which the setup was then investigated for grid convergence using different mesh resolutions. Mesh convergence was investigated using different tools and observing residuals for each parameter, providing a better understanding of flow behaviour versus simulation time required. The chosen mesh was based on its accuracy and simulation time. The simulated data for point injection of O2 were compared to the field results of Madsen et al. (2006), showing good agreement. The same setup was then used for the study to investigate the effects of suction on O2 removal. It not only provided insights into system dynamics, but also is of practical benefit for identifying potential hotspots for H2S and designing strategies for H2S removal. Chapter 6 aimed to establish the relationship between mass transfer and turbulence level by varying the stirring rates in a rotating system. Dynamic meshing was employed for the setup, designed to scale with the experiments conducted by Pacheco Fernández et al. (2020). Multiple mesh tests were performed to achieve grid convergence, and the chosen mesh exhibited good results with optimal computation time. Both solvers showed an increase in mass transfer with higher stirring rates which is consistent with previous research. The time series for concentration of simulated data for H2S and O2 aligned well with measured data, providing valuable information on mass transfer operations in highly turbulent systems. The extended CFD model offers a comprehensive approach to better understand and predict the distribution of H2S and O2 in sewer systems and can serve as a decision support tool for odour control in sewers.","abstract_html":"Sewer networks are integral infrastructures in a well-planned city. Their vital role lies in efficiently transporting both wastewater to treatment facilities and rainwater from residential areas. The emission of hydrogen sulphide (H2S) combined with the oxygen (O2) present in the system can pose a significant threat to the integrity of concrete channels which is amplified for older sewer systems. Not only can its release lead to the erosion of sewer walls due to concrete corrosion, but it also presents a safety hazard for those working in the sewer environment. Not to mention the accompanying high costs for maintenance to mitigate these problems. The generation of hydrogen sulphide and the concentration of oxygen in sewers are influenced by various factors, including turbulent flow conditions, hydraulic retention time, flow velocities, and pH value. Numerical modeling with Computational Fluid Dynamics (CFD) software provides a valuable tool for studying multiphase flows and understanding the complex interactions between fluid dynamics and chemical processes. This doctoral thesis focuses firstly on validating the air phase flow in the sewer headspace. The solver for simulating mass transfer of H2S developed by Teuber (2020) in the OpenFOAM framework is further validated and then extended and validated to account for O2. Simulations of the high-resolution models were carried out on a high-performance computing cluster. Chapter 1 of this thesis deal with the general introduction to the problems of odour and corrosion in sewer systems, while chapter 2 provides a concise summary of the model's principles and tools used, along with the developed solver extensions. In Chapter 3 the updated and extended solvers, interH2SFoam and interO2Foam respectively, are validated using a quasi-steady state tank. These solvers accurately reproduced concentration profiles and equilibrium concentrations based on Henry's law, including the temperature-dependent behaviour of the Henry coefficient. In Chapter 4, the volume-of-fluid (VOF) approach implemented in OpenFOAM was applied to analyze two-phase flow hydraulics in a lab-scale rectangular duct. The interH2SFoam solver was further validated for turbulent conditions later in the chapter, with results compared to the results of Teuber et al. (2019b) showing good agreement. To validate the capability of the interO2Foam solver for gas transport in sewer headspace, experimental data from Bentzen et al. (2016) was used. Simulated results were compared to experimental data and a 1D analytical solution for transport, yielding acceptable agreement. In Chapter 5, the interO2Foam solver was validated using the field study of Madsen et al. (2006). The interFoam solver achieved a hydraulically steady state and was validated against analytical data. After which the setup was then investigated for grid convergence using different mesh resolutions. Mesh convergence was investigated using different tools and observing residuals for each parameter, providing a better understanding of flow behaviour versus simulation time required. The chosen mesh was based on its accuracy and simulation time. The simulated data for point injection of O2 were compared to the field results of Madsen et al. (2006), showing good agreement. The same setup was then used for the study to investigate the effects of suction on O2 removal. It not only provided insights into system dynamics, but also is of practical benefit for identifying potential hotspots for H2S and designing strategies for H2S removal. Chapter 6 aimed to establish the relationship between mass transfer and turbulence level by varying the stirring rates in a rotating system. Dynamic meshing was employed for the setup, designed to scale with the experiments conducted by Pacheco Fernández et al. (2020). Multiple mesh tests were performed to achieve grid convergence, and the chosen mesh exhibited good results with optimal computation time. Both solvers showed an increase in mass transfer with higher stirring rates which is consistent with previous research. The time series for concentration of simulated data for H2S and O2 aligned well with measured data, providing valuable information on mass transfer operations in highly turbulent systems. The extended CFD model offers a comprehensive approach to better understand and predict the distribution of H2S and O2 in sewer systems and can serve as a decision support tool for odour control in sewers.","abstract_has_math":false,"creators":["Dixit, Abhinav"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Hinkelmann, Reinhard"],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024","date_published":"2024","updated_at":"2026-07-27T21:28:49Z","subjects":[],"languages":["en"],"rights":[],"rights_urls":["https://creativecommons.org/licenses/by/4.0/"],"identifier_entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://doi.org/10.14279/depositonce-19857"],"render_values":[{"text":"https://doi.org/10.14279/depositonce-19857","href":"https://doi.org/10.14279/depositonce-19857","code":true}]}]},"links":{"outbound_url":"https://depositonce.tu-berlin.de/handle/11303/21057","outbound_label":"Repository record","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Hinkelmann, Reinhard"]},{"key":"dc:creator","label":"Author","values":["Dixit, Abhinav"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2024-02-27T08:38:13Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2024-02-27T08:38:13Z"]},{"key":"dc:date.issued","label":"Date","values":["2024"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights.uri","label":"Rights URI","values":["https://creativecommons.org/licenses/by/4.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://depositonce.tu-berlin.de/handle/11303/21057","https://doi.org/10.14279/depositonce-19857"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Sewer networks are integral infrastructures in a well-planned city. Their vital role lies in efficiently transporting both wastewater to treatment facilities and rainwater from residential areas. The emission of hydrogen sulphide (H2S) combined with the oxygen (O2) present in the system can pose a significant threat to the integrity of concrete channels which is amplified for older sewer systems. Not only can its release lead to the erosion of sewer walls due to concrete corrosion, but it also presents a safety hazard for those working in the sewer environment. Not to mention the accompanying high costs for maintenance to mitigate these problems. The generation of hydrogen sulphide and the concentration of oxygen in sewers are influenced by various factors, including turbulent flow conditions, hydraulic retention time, flow velocities, and pH value. Numerical modeling with Computational Fluid Dynamics (CFD) software provides a valuable tool for studying multiphase flows and understanding the complex interactions between fluid dynamics and chemical processes. This doctoral thesis focuses firstly on validating the air phase flow in the sewer headspace. The solver for simulating mass transfer of H2S developed by Teuber (2020) in the OpenFOAM framework is further validated and then extended and validated to account for O2. Simulations of the high-resolution models were carried out on a high-performance computing cluster. Chapter 1 of this thesis deal with the general introduction to the problems of odour and corrosion in sewer systems, while chapter 2 provides a concise summary of the model's principles and tools used, along with the developed solver extensions. In Chapter 3 the updated and extended solvers, interH2SFoam and interO2Foam respectively, are validated using a quasi-steady state tank. These solvers accurately reproduced concentration profiles and equilibrium concentrations based on Henry's law, including the temperature-dependent behaviour of the Henry coefficient. In Chapter 4, the volume-of-fluid (VOF) approach implemented in OpenFOAM was applied to analyze two-phase flow hydraulics in a lab-scale rectangular duct. The interH2SFoam solver was further validated for turbulent conditions later in the chapter, with results compared to the results of Teuber et al. (2019b) showing good agreement. To validate the capability of the interO2Foam solver for gas transport in sewer headspace, experimental data from Bentzen et al. (2016) was used. Simulated results were compared to experimental data and a 1D analytical solution for transport, yielding acceptable agreement. In Chapter 5, the interO2Foam solver was validated using the field study of Madsen et al. (2006). The interFoam solver achieved a hydraulically steady state and was validated against analytical data. After which the setup was then investigated for grid convergence using different mesh resolutions. Mesh convergence was investigated using different tools and observing residuals for each parameter, providing a better understanding of flow behaviour versus simulation time required. The chosen mesh was based on its accuracy and simulation time. The simulated data for point injection of O2 were compared to the field results of Madsen et al. (2006), showing good agreement. The same setup was then used for the study to investigate the effects of suction on O2 removal. It not only provided insights into system dynamics, but also is of practical benefit for identifying potential hotspots for H2S and designing strategies for H2S removal. Chapter 6 aimed to establish the relationship between mass transfer and turbulence level by varying the stirring rates in a rotating system. Dynamic meshing was employed for the setup, designed to scale with the experiments conducted by Pacheco Fernández et al. (2020). Multiple mesh tests were performed to achieve grid convergence, and the chosen mesh exhibited good results with optimal computation time. Both solvers showed an increase in mass transfer with higher stirring rates which is consistent with previous research. The time series for concentration of simulated data for H2S and O2 aligned well with measured data, providing valuable information on mass transfer operations in highly turbulent systems. The extended CFD model offers a comprehensive approach to better understand and predict the distribution of H2S and O2 in sewer systems and can serve as a decision support tool for odour control in sewers.","Kanalisationssysteme sind ein wichtiger Bestandteil der städtischen Infrastruktur. Sie spielen eine elementare Rolle bei der Ableitung von Abwässern zu Kläranlagen sowie bei der Entwässerung von Wohngebieten. Die Freisetzung von Schwefelwasserstoff (H2S) in Verbindung mit dem in den Systemen vorhandenen Sauerstoff (O2) stellt eine erhebliche Gefährdung von Abwasserkanälen dar, insbesondere in alten Systemen, da die Freisetzung von H2S nicht nur zur Schädigung von Kanalwänden aufgrund von Betonkorrosion führt, sondern sie stellt auch ein Sicherheitsrisiko für die in der Kanalisation arbeitenden Personen dar. Die damit einhergehenden hohen Instandhaltungskosten sind waren und sind beträchtlich. Die Bildung von Schwefelwasserstoff und die Konzentration von Sauerstoff in Abwasserkanälen werden von verschiedenen Faktoren beeinflusst, darunter das Abflussregime, hydraulische Verweilzeiten, Fließgeschwindigkeiten und der pH-Wert. Die numerische Modellierung mit Computational Fluid Dynamics (CFD)-Software ist ein wertvolles Instrument zur Untersuchung von Mehrphasenströmungen und um die komplexen Wechselwirkungen zwischen der Fluiddynamik und chemischen Prozessen besser zu verstehen. Zu Beginn der Dissertation wird die Validierung der Luftphasenströmung behandelt. In einem ersten Schritt wird der von Teuber (2020) innerhalb des OpenFOAM Frameworks entwickelte Löser zur Simulation von H2S-Stofftransport weiter validiert. Anschlie?end wird das System um die O2-Komponente erweitert und ebenfalls validiert. Aufgrund der hohen Rechenanforderungen der hochauflösenden Modelle wurden für alle Simulationen Hochleistungsrechner verwendet. Kapitel 1 dieser Arbeit befasst sich mit einer allgemeinen Einführung in das Thema Geruch und Korrosion in Abwassersystemen. Kapitel 2 bietet eine kurze Übersicht über die Modellkonzepte und -werkzeuge, die verwendet wurden, sowie über die vorgenommenen Modifikationen am Solver. In Kapitel 3 wurden die aktualisierten und erweiterten Solver, interH2SFoam und interO2Foam, in einem quasistationären Tank validiert. Konzentrationsprofile und Gleichgewichtskonzentrationen basierend auf dem Henry-Gestz wurden präzise reproduziert, einschließlich des temperaturabhängigen Verhaltens des Henry-Koeffizienten. In Kapitel 4 wurde der in OpenFOAM implementierte Volume-of-Fluid (VoF) Ansatz verwendet, um die Hydraulik der Zweiphasenströmung in einem rechteckigen Kanal im Labormaßstab zu analysieren. Der interH2SFoam Löser wurde erfolgreich für ein turbulentes Abflussregime validiert, wobei die Ergebnisse eine gute Übereinstimmung mit den Ergebnissen von Teuber et al. (2019b) zeigten. Zur Validierung der Fähigkeit des interO2Foam-Lösers für den Gastransport in der Luft im Abwasserkanal wurden die experimentellen Daten von Bentzen et al. (2016) herangezogen, mit welchen die Simulationsergebnisse eine akzeptable Übereinstimmung zeigten. In Kapitel 5 erfolgte die Validierung des interO2Foam-Solvers anhand der Feldstudie von Madsen et al. (2006). Es wurde ein hydraulisch stationärer Zustand simuliert, welcher zunächst anhand analytischer Daten validiert wurde. Anschließend wurde die Gitterkonvergenz anhand verschiedener Strömungsvariablen untersucht, um ein besseres Verständnis des Strömungsverhaltens in Bezug auf die erforderliche Simulationszeit zu erlangen. Die Wahl des Gitters erfolgte auf der Grundlage von Genauigkeit und Simulationszeit. Die simulierten Daten für die punktuelle Injektion von O2 wurden mit den physikalischen Ergebnissen von Madsen et al. (2006) verglichen und zeigten eine gute Übereinstimmung. Anschließend wurde eine Studie zur Absaugung von O2 durchgeführt, wodurch zum einen weitere Einblicke in die Systemdynamik und zum anderen praktische Erkenntnisse zur Reduktion der Geruchs- und Korrosionsproblematik gewonnen wurden. Kapitel 6 zielte darauf ab, die Beziehung zwischen Massentransfer und Turbulenzgrad durch Variation der Rührgeschwindigkeiten in einem rotierenden System zu ermitteln. Für den Aufbau wurde ein dynamisches Gitternetz verwendet undes wurden Experimente von Pacheco Fernández et al. (2020) simuliert. Mehrere Gittertests wurden durchgeführt, um die Gitterkonvergenz zu erreichen, wobei das ausgewählte Gitter gute Ergebnisse bei angemessener Berechnungszeit lieferte. Beide Löser berechneten eine Zunahme des Massentransfers bei höheren Rührgeschwindigkeiten, was mit vorherigen Untersuchungen übereinstimmte. Die Zeitreihen der simulierten Konzentrationen von H2S und O2 stimmten gut mit den gemessenen Daten überein und lieferten wertvolle Informationen über den Massentransfer in hochturbulenten Systemen. Das erweiterte CFD Modell bietet einen umfassenden Ansatz zum verbesserten Verständnis und zur Untersuchung von H2S und O2 in Abwassersystemen und kann somitals Entscheidungshilfe für die Geruchskontrolle in Abwasserkanälen herangezogen werden."]},{"key":"dc:title","label":"Title","values":["Extension and further validation of a 3D two-phase flow model for flow, transport and mass transfer in sewer systems"]}]}],"canonical_facts":{"dc:contributor.advisor":["Hinkelmann, Reinhard"],"dc:creator":["Dixit, Abhinav"],"dc:date.accessioned":["2024-02-27T08:38:13Z"],"dc:date.available":["2024-02-27T08:38:13Z"],"dc:date.issued":["2024"],"dc:description.abstract":["Sewer networks are integral infrastructures in a well-planned city. Their vital role lies in efficiently transporting both wastewater to treatment facilities and rainwater from residential areas. The emission of hydrogen sulphide (H2S) combined with the oxygen (O2) present in the system can pose a significant threat to the integrity of concrete channels which is amplified for older sewer systems. Not only can its release lead to the erosion of sewer walls due to concrete corrosion, but it also presents a safety hazard for those working in the sewer environment. Not to mention the accompanying high costs for maintenance to mitigate these problems. The generation of hydrogen sulphide and the concentration of oxygen in sewers are influenced by various factors, including turbulent flow conditions, hydraulic retention time, flow velocities, and pH value. Numerical modeling with Computational Fluid Dynamics (CFD) software provides a valuable tool for studying multiphase flows and understanding the complex interactions between fluid dynamics and chemical processes. This doctoral thesis focuses firstly on validating the air phase flow in the sewer headspace. The solver for simulating mass transfer of H2S developed by Teuber (2020) in the OpenFOAM framework is further validated and then extended and validated to account for O2. Simulations of the high-resolution models were carried out on a high-performance computing cluster. Chapter 1 of this thesis deal with the general introduction to the problems of odour and corrosion in sewer systems, while chapter 2 provides a concise summary of the model's principles and tools used, along with the developed solver extensions. In Chapter 3 the updated and extended solvers, interH2SFoam and interO2Foam respectively, are validated using a quasi-steady state tank. These solvers accurately reproduced concentration profiles and equilibrium concentrations based on Henry's law, including the temperature-dependent behaviour of the Henry coefficient. In Chapter 4, the volume-of-fluid (VOF) approach implemented in OpenFOAM was applied to analyze two-phase flow hydraulics in a lab-scale rectangular duct. The interH2SFoam solver was further validated for turbulent conditions later in the chapter, with results compared to the results of Teuber et al. (2019b) showing good agreement. To validate the capability of the interO2Foam solver for gas transport in sewer headspace, experimental data from Bentzen et al. (2016) was used. Simulated results were compared to experimental data and a 1D analytical solution for transport, yielding acceptable agreement. In Chapter 5, the interO2Foam solver was validated using the field study of Madsen et al. (2006). The interFoam solver achieved a hydraulically steady state and was validated against analytical data. After which the setup was then investigated for grid convergence using different mesh resolutions. Mesh convergence was investigated using different tools and observing residuals for each parameter, providing a better understanding of flow behaviour versus simulation time required. The chosen mesh was based on its accuracy and simulation time. The simulated data for point injection of O2 were compared to the field results of Madsen et al. (2006), showing good agreement. The same setup was then used for the study to investigate the effects of suction on O2 removal. It not only provided insights into system dynamics, but also is of practical benefit for identifying potential hotspots for H2S and designing strategies for H2S removal. Chapter 6 aimed to establish the relationship between mass transfer and turbulence level by varying the stirring rates in a rotating system. Dynamic meshing was employed for the setup, designed to scale with the experiments conducted by Pacheco Fernández et al. (2020). Multiple mesh tests were performed to achieve grid convergence, and the chosen mesh exhibited good results with optimal computation time. Both solvers showed an increase in mass transfer with higher stirring rates which is consistent with previous research. The time series for concentration of simulated data for H2S and O2 aligned well with measured data, providing valuable information on mass transfer operations in highly turbulent systems. The extended CFD model offers a comprehensive approach to better understand and predict the distribution of H2S and O2 in sewer systems and can serve as a decision support tool for odour control in sewers.","Kanalisationssysteme sind ein wichtiger Bestandteil der städtischen Infrastruktur. Sie spielen eine elementare Rolle bei der Ableitung von Abwässern zu Kläranlagen sowie bei der Entwässerung von Wohngebieten. Die Freisetzung von Schwefelwasserstoff (H2S) in Verbindung mit dem in den Systemen vorhandenen Sauerstoff (O2) stellt eine erhebliche Gefährdung von Abwasserkanälen dar, insbesondere in alten Systemen, da die Freisetzung von H2S nicht nur zur Schädigung von Kanalwänden aufgrund von Betonkorrosion führt, sondern sie stellt auch ein Sicherheitsrisiko für die in der Kanalisation arbeitenden Personen dar. Die damit einhergehenden hohen Instandhaltungskosten sind waren und sind beträchtlich. Die Bildung von Schwefelwasserstoff und die Konzentration von Sauerstoff in Abwasserkanälen werden von verschiedenen Faktoren beeinflusst, darunter das Abflussregime, hydraulische Verweilzeiten, Fließgeschwindigkeiten und der pH-Wert. Die numerische Modellierung mit Computational Fluid Dynamics (CFD)-Software ist ein wertvolles Instrument zur Untersuchung von Mehrphasenströmungen und um die komplexen Wechselwirkungen zwischen der Fluiddynamik und chemischen Prozessen besser zu verstehen. Zu Beginn der Dissertation wird die Validierung der Luftphasenströmung behandelt. In einem ersten Schritt wird der von Teuber (2020) innerhalb des OpenFOAM Frameworks entwickelte Löser zur Simulation von H2S-Stofftransport weiter validiert. Anschlie?end wird das System um die O2-Komponente erweitert und ebenfalls validiert. Aufgrund der hohen Rechenanforderungen der hochauflösenden Modelle wurden für alle Simulationen Hochleistungsrechner verwendet. Kapitel 1 dieser Arbeit befasst sich mit einer allgemeinen Einführung in das Thema Geruch und Korrosion in Abwassersystemen. Kapitel 2 bietet eine kurze Übersicht über die Modellkonzepte und -werkzeuge, die verwendet wurden, sowie über die vorgenommenen Modifikationen am Solver. In Kapitel 3 wurden die aktualisierten und erweiterten Solver, interH2SFoam und interO2Foam, in einem quasistationären Tank validiert. Konzentrationsprofile und Gleichgewichtskonzentrationen basierend auf dem Henry-Gestz wurden präzise reproduziert, einschließlich des temperaturabhängigen Verhaltens des Henry-Koeffizienten. In Kapitel 4 wurde der in OpenFOAM implementierte Volume-of-Fluid (VoF) Ansatz verwendet, um die Hydraulik der Zweiphasenströmung in einem rechteckigen Kanal im Labormaßstab zu analysieren. Der interH2SFoam Löser wurde erfolgreich für ein turbulentes Abflussregime validiert, wobei die Ergebnisse eine gute Übereinstimmung mit den Ergebnissen von Teuber et al. (2019b) zeigten. Zur Validierung der Fähigkeit des interO2Foam-Lösers für den Gastransport in der Luft im Abwasserkanal wurden die experimentellen Daten von Bentzen et al. (2016) herangezogen, mit welchen die Simulationsergebnisse eine akzeptable Übereinstimmung zeigten. In Kapitel 5 erfolgte die Validierung des interO2Foam-Solvers anhand der Feldstudie von Madsen et al. (2006). Es wurde ein hydraulisch stationärer Zustand simuliert, welcher zunächst anhand analytischer Daten validiert wurde. Anschließend wurde die Gitterkonvergenz anhand verschiedener Strömungsvariablen untersucht, um ein besseres Verständnis des Strömungsverhaltens in Bezug auf die erforderliche Simulationszeit zu erlangen. Die Wahl des Gitters erfolgte auf der Grundlage von Genauigkeit und Simulationszeit. Die simulierten Daten für die punktuelle Injektion von O2 wurden mit den physikalischen Ergebnissen von Madsen et al. (2006) verglichen und zeigten eine gute Übereinstimmung. Anschließend wurde eine Studie zur Absaugung von O2 durchgeführt, wodurch zum einen weitere Einblicke in die Systemdynamik und zum anderen praktische Erkenntnisse zur Reduktion der Geruchs- und Korrosionsproblematik gewonnen wurden. Kapitel 6 zielte darauf ab, die Beziehung zwischen Massentransfer und Turbulenzgrad durch Variation der Rührgeschwindigkeiten in einem rotierenden System zu ermitteln. Für den Aufbau wurde ein dynamisches Gitternetz verwendet undes wurden Experimente von Pacheco Fernández et al. (2020) simuliert. Mehrere Gittertests wurden durchgeführt, um die Gitterkonvergenz zu erreichen, wobei das ausgewählte Gitter gute Ergebnisse bei angemessener Berechnungszeit lieferte. Beide Löser berechneten eine Zunahme des Massentransfers bei höheren Rührgeschwindigkeiten, was mit vorherigen Untersuchungen übereinstimmte. Die Zeitreihen der simulierten Konzentrationen von H2S und O2 stimmten gut mit den gemessenen Daten überein und lieferten wertvolle Informationen über den Massentransfer in hochturbulenten Systemen. Das erweiterte CFD Modell bietet einen umfassenden Ansatz zum verbesserten Verständnis und zur Untersuchung von H2S und O2 in Abwassersystemen und kann somitals Entscheidungshilfe für die Geruchskontrolle in Abwasserkanälen herangezogen werden."],"dc:identifier.uri":["https://depositonce.tu-berlin.de/handle/11303/21057","https://doi.org/10.14279/depositonce-19857"],"dc:language.iso":["en"],"dc:rights.uri":["https://creativecommons.org/licenses/by/4.0/"],"dc:title":["Extension and further validation of a 3D two-phase flow model for flow, transport and mass transfer in sewer systems"],"dc:type":["Doctoral Thesis"]},"updated_at":"2026-07-27T21:28:49Z"}