Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
A modified k-ω turbulence model for improved predictions of neutral atmospheric boundary layer flows
https://orcid.org/0000-0002-7082-3083
https://orcid.org/0000-0002-6108-467X
https://orcid.org/0000-0002-7812-4498
Abstract A modified k-ω turbulence model is developed for neutral atmospheric boundary layer flows by introducing additional source terms to the equations of the standard model to remove its inconsistency with the inlet conditions. Rough wall functions based on aerodynamic roughness are adopted to overcome the limitations of the standard wall functions that are based on sand grain roughness. Moreover, the diagnostic and prognostic approaches are considered when simulating the flow. The diagnostic approach is approximate, relying on satisfying mass conservation by solving an optimization problem, whereas the prognostic approach resolves the Navier-Stokes equations with a turbulence model. The performances of the developed modified k-ω model, an existing modified k-ε model, and the standard SST k-ω model are compared. To calculate the concentration field, the Eulerian approach which solves a concentration transport equation, and the Lagrangian approach which adopts the particle method with core radius spreading for computing diffusion are used. Results generated with the diagnostic approach demonstrate its unsuitability to calculate wind flows over complex geometries. On the other hand, the prognostic approach, with the three mentioned turbulence models, was successful in reproducing the flow data of CEDVAL A1 and B1 experiments in domains composed of one building and an array of buildings. In addition, a good agreement with the concentration measurements is obtained when using the newly modified k-ω and the SST k-ω models to account for turbulence, with the Eulerian method outperforming the Lagrangian dispersion approach.
Highlights Developing a new modified k-ω turbulence model for atmospheric boundary layer flows (ABL). Implementation, within a homemade unstructured, three-dimensional pressure-based solver, following the FVM. Comparing the performance of the diagnostic and prognostic approaches for predicting ABL flows in urban environments. Modeling pollution dispersion using Eulerian-Eulerian and Eulerian-Lagrangian computations. Comparing the k-ε, k-ω, and k-ω SST turbulence models for predicting pollution dispersion in urban environments.
A modified k-ω turbulence model for improved predictions of neutral atmospheric boundary layer flows
https://orcid.org/0000-0002-7082-3083
https://orcid.org/0000-0002-6108-467X
https://orcid.org/0000-0002-7812-4498
Abstract A modified k-ω turbulence model is developed for neutral atmospheric boundary layer flows by introducing additional source terms to the equations of the standard model to remove its inconsistency with the inlet conditions. Rough wall functions based on aerodynamic roughness are adopted to overcome the limitations of the standard wall functions that are based on sand grain roughness. Moreover, the diagnostic and prognostic approaches are considered when simulating the flow. The diagnostic approach is approximate, relying on satisfying mass conservation by solving an optimization problem, whereas the prognostic approach resolves the Navier-Stokes equations with a turbulence model. The performances of the developed modified k-ω model, an existing modified k-ε model, and the standard SST k-ω model are compared. To calculate the concentration field, the Eulerian approach which solves a concentration transport equation, and the Lagrangian approach which adopts the particle method with core radius spreading for computing diffusion are used. Results generated with the diagnostic approach demonstrate its unsuitability to calculate wind flows over complex geometries. On the other hand, the prognostic approach, with the three mentioned turbulence models, was successful in reproducing the flow data of CEDVAL A1 and B1 experiments in domains composed of one building and an array of buildings. In addition, a good agreement with the concentration measurements is obtained when using the newly modified k-ω and the SST k-ω models to account for turbulence, with the Eulerian method outperforming the Lagrangian dispersion approach.
Highlights Developing a new modified k-ω turbulence model for atmospheric boundary layer flows (ABL). Implementation, within a homemade unstructured, three-dimensional pressure-based solver, following the FVM. Comparing the performance of the diagnostic and prognostic approaches for predicting ABL flows in urban environments. Modeling pollution dispersion using Eulerian-Eulerian and Eulerian-Lagrangian computations. Comparing the k-ε, k-ω, and k-ω SST turbulence models for predicting pollution dispersion in urban environments.
A modified k-ω turbulence model for improved predictions of neutral atmospheric boundary layer flows
https://orcid.org/0000-0002-7082-3083
https://orcid.org/0000-0002-6108-467X
https://orcid.org/0000-0002-7812-4498
Abstract A modified k-ω turbulence model is developed for neutral atmospheric boundary layer flows by introducing additional source terms to the equations of the standard model to remove its inconsistency with the inlet conditions. Rough wall functions based on aerodynamic roughness are adopted to overcome the limitations of the standard wall functions that are based on sand grain roughness. Moreover, the diagnostic and prognostic approaches are considered when simulating the flow. The diagnostic approach is approximate, relying on satisfying mass conservation by solving an optimization problem, whereas the prognostic approach resolves the Navier-Stokes equations with a turbulence model. The performances of the developed modified k-ω model, an existing modified k-ε model, and the standard SST k-ω model are compared. To calculate the concentration field, the Eulerian approach which solves a concentration transport equation, and the Lagrangian approach which adopts the particle method with core radius spreading for computing diffusion are used. Results generated with the diagnostic approach demonstrate its unsuitability to calculate wind flows over complex geometries. On the other hand, the prognostic approach, with the three mentioned turbulence models, was successful in reproducing the flow data of CEDVAL A1 and B1 experiments in domains composed of one building and an array of buildings. In addition, a good agreement with the concentration measurements is obtained when using the newly modified k-ω and the SST k-ω models to account for turbulence, with the Eulerian method outperforming the Lagrangian dispersion approach.
Highlights Developing a new modified k-ω turbulence model for atmospheric boundary layer flows (ABL). Implementation, within a homemade unstructured, three-dimensional pressure-based solver, following the FVM. Comparing the performance of the diagnostic and prognostic approaches for predicting ABL flows in urban environments. Modeling pollution dispersion using Eulerian-Eulerian and Eulerian-Lagrangian computations. Comparing the k-ε, k-ω, and k-ω SST turbulence models for predicting pollution dispersion in urban environments.
A modified k-ω turbulence model for improved predictions of neutral atmospheric boundary layer flows
Saleh, A. (Autor:in) / Lakkis, I. (Autor:in) / Moukalled, F. (Autor:in)
Building and Environment ; 223
10.08.2022
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
Sediment-Turbulence Interaction in Boundary Layer Flows
| British Library Conference Proceedings | 1995