Banca de DEFESA: ABLAIL PAULA PINHEIRO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ABLAIL PAULA PINHEIRO
DATE: 30/08/2021
TIME: 14:00
LOCAL: https://youtu.be/L7IreYVQyVY
TITLE:

CAPTURE OF TURBULENCE EFFECTS OF FISHPASS RECIRCULATIONS BY RANS AND LES MODELS

KEY WORDS:

Open channel; Computational Fluid Dynamics; OpenFOAM; Turbulence

PAGES: 100
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Engenharia Hidráulica
SPECIALTY: Hidráulica
SUMMARY:

Turbulence is a phenomenon in which the fluid particles mix disorderly and where there are instantaneous fluctuations in velocities that are irregular and apparently random. The application of numerical models for the analysis of the flow in transposition structures of the ichthyofauna allows for a better understanding of turbulent flow. Turbulence is a notable aspect for explaining fish movement, as turbulent flow can produce different effects on it. Beyond how turbulent the runoff is, fish can be attracted or repelled, helping or slowing their migratory movements. The RANS equations (Reynolds Averaged Navier Stokes) with the K-ε turbulence model have been the main numerical model to characterize the flow in fish passages. More recently, a LES (Large Eddy Simulation) simulation was reported to be better for characterizing turbulence in incompressible flows. Thus, this work aimed to evaluate whether the numerical models RANS and LES are able to capture the turbulence effects of a free surface hydraulic flow measured in two physical model: 1) fish ladder of central vertical slot in reduced scale, and 2) circular channel for fish juvenile and eggs . Therefore, a Computational Fluid Dynamics (CFD) model was developed using OpenFOAM software and the Volume of Fluid (VOF) method was used to determine the free surface of the flow. In order to validate the model, velocity measurements with ADV (Acoustic Doppler Velocimeter) were made to compare and adjust the results of the simulations. The LES kEqn model was better than RANS k-ε in representing turbulence. An application of the LES model in flumes will be useful to improve the understanding of fish passage performance.

BANKING MEMBERS:
Interna - HERSILIA DE ANDRADE E SANTOS
Interno - LINEKER MAX GOULART COELHO
Externa à Instituição - DANIELA GUZZON SANAGIOTTO - UFRGS
Externo à Instituição - RICARDO AHOUAGI CARNEIRO JUNHO