Study of skimming flow in flat slope stepped channels

In this thesis, the results of a numerical modeling study that addresses the skimming flow properties in flat slope stepped channels, are presented and analyzed. Experimental data of mean flow velocity profiles from Hunt and Kadavy's physical model was used for the calibration of the results ob...

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Autores:
López de Mesa Aguilar, Daniel
Tipo de recurso:
Fecha de publicación:
2017
Institución:
Universidad Nacional de Colombia
Repositorio:
Universidad Nacional de Colombia
Idioma:
spa
OAI Identifier:
oai:repositorio.unal.edu.co:unal/63675
Acceso en línea:
https://repositorio.unal.edu.co/handle/unal/63675
http://bdigital.unal.edu.co/64126/
Palabra clave:
6 Tecnología (ciencias aplicadas) / Technology
62 Ingeniería y operaciones afines / Engineering
Flat slope stepped spillways
Skimming flow
Aerated flow
Non-aerated flow
Turbulence modeling
Multiphase flow modeling
SST k-omega model
Mixture model
Viscous sub-layer
Log-law region
Descargas escalonadas de baja pendiente
Flujo rasante
Flujo aireado
Flujo no aireado
Modelado de la turbulencia
Modelado del flujo multifásico
Modelo SST k-omega
Modelo "Mixture"
Sub-capa viscosa
Capa logarítmica
Rights
openAccess
License
Atribución-NoComercial 4.0 Internacional
Description
Summary:In this thesis, the results of a numerical modeling study that addresses the skimming flow properties in flat slope stepped channels, are presented and analyzed. Experimental data of mean flow velocity profiles from Hunt and Kadavy's physical model was used for the calibration of the results obtained with a numerical model performed with the commercial CFD tool: Ansys Fluent. SST k-omega was selected for turbulence modeling and Mixture model for the free surface tracking process, but as the flow aeration downstream the inception point wasn't captured by the mentioned models, a "data adjustment procedure" was proposed to be able to compare the experimental data from measuring stations with air entrance, with the numerical results. This work presents a hydrodynamical diagnosis addressing the relations between the mean flow velocity, static pressure, turbulent kinetic energy production and viscous dissipation rates along the skimming flow domain. Additional runs with wall roughness, riser height (h) and tread length (l) variations were performed to conclude about the effects in the mentioned hydrodynamical variables.