Navegando por Autor "Petry, Adriane Prisco"

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Estudio numérico de flujos turbulentos isotérmicos en canales y flujos laminares con convección mixta en cavidades
(2011) Santos, Elizaldo Domingues dos; Xavier, Carla Maria; Petry, Adriane Prisco
Se ha realizado un estudio numérico sobre flujos estacionarios turbulentos, en canales tridimensionales y flujos transitorios laminares en cavidades con transferencia de calor por convección mixta. Las ecuaciones de conservación se resuelven a través del Método de Elementos Finitos utilizando esquema temporal explicito de Taylor-Galerkin. La simulación de Grandes Escalas se emplea para el tratamiento de la turbulencia. Para el caso isotérmico, flujos con Re = 3300 son simulados usando los modelos submalla de Smagorinsky y Dinámico. Este último modelo permitió mejorar los perfiles de velocidad media y las estadísticas de la turbulencia. Los campos transitorios de velocidad y temperatura se compararon con los resultados de la literatura, obteniéndose un desvío inferior a 6%.
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Estudio numérico de flujos turbulentos isotérmicos en canales y flujos laminares con convección mixta en cavidades
(2011) Santos, Elizaldo Domingues dos; Xavier, Carla Maria; Petry, Adriane Prisco
A numerical study about three-dimensional steady state turbulent channel flows and laminar transient cavity flows with mixed convection heat transfer has been done. The solution of the conservation equations is obtained by means of Finite Element Method and Taylor-Galerkin explicit scheme. Large Eddy Simulation is employed for the treatment of turbulence. For the isothermal case, flows with Re = 3300 were simulated using the Smagorinsky and Dynamical subgrid models. The latter model allowed improving the average velocity profiles as well as turbulence statistics. The transient velocity and temperature fields were compared with results of the literature, leading to a deviation lower than 6%.
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A numerical study of combined convective and radiative heat transfer in non-reactive turbulent channel flows with several optical thicknesses: a comparison between LES and RANS
(2014) Santos, Elizaldo Domingues dos; Isoldi, Liércio André; Petry, Adriane Prisco; França, Francis Henrique Ramos
This work presents a numerical study of turbulent channel flows with combined convective and radiative heat transfer in participating media by means of large Eddy simulation and Reynolds averaged Navier–Stokes (RANS) with k–ε model. The main purpose is to evaluate the employment of the traditional modeling (RANS without TRI) for the prediction of time-averaged parameters of turbulent non-reactive flows with convective and radiative heat transfer. All cases are investigated with Re τ = 180, Pr = 0.71 and for various optical thicknesses: τ 0 = 0.01, 0.1, 1.0, 10 and 100. In spite of the consideration of non-relevance of turbulence–radiation interactions for non-reactive turbulent flows, the results shown that for τ 0 ≥10 the employment of RANS with k–ε model led to considerable deviations for the prediction of time-averaged radiative fluxes and divergence of the radiative fluxes. For τ 0 = 100, both models also led to different results for the time-averaged convective fluxes.
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Numerical study of forced convection lid-driven cavity flows using LES (Large Eddy Simulation)
(2013) Santos, Elizaldo Domingues dos; Petry, Adriane Prisco; Rocha, Luiz Alberto Oliveira; França, Francis Henrique Ramos
This study presents the LES (large eddy simulation) of forced convection in laminar and two dimensional turbulent flows when the flow reaches the steady state. The main purpose is the evaluation of a developed numerical methodology for the simulation of forced convection flows at various Reynolds numbers (100 ≤ ReH ≤ 10,000) and for a fixed Prandtl number (Pr = 1.0). The hexahedral eight-node FEM (finite element method) with an explicit Taylor-Galerkin scheme is used to obtain the numerical solutions of the conservation equations of mass, momentum and energy. The Smagorinsky model is employed for the sub-grid treatment. The time-averaged velocity and temperature profiles are compared with results of literature and a CFD (computational fluid dynamics) package based on finite volume method, leading to a highest deviation of nearly 6%. Moreover, characteristics of the forced convection flows are properly obtained, e.g., the effect of the Reynolds number over the multiplicity of scales.
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A numerical study of the influence of temperature fluctuations in the thermal radiation field
(2009) Santos, Elizaldo Domingues dos; Galarça, Marcelo Moraes; Mossi, Anderson Chaves; Petry, Adriane Prisco; França, Francis Henrique Ramos
The present paper performs a numerical study of the influence of fluctuations on the temperature field over the thermal radiation field with the purpose to simulate the effect of Turbulence-Radiation Interactions (TRI). To evaluate the behavior of the divergence of the radiant heat flux for a flame in a cylindrical cavity, four temperature profiles are imposed: na average temperature profile and other three with 10%, 20% and 30% of turbulence intensity. The radiative transfer equation is solved using the discrete ordinates method (DOM) and the participating medium is treated as a gray gas. The results demonstrate that the fluctuations of temperature profiles increase significantly the mean divergence of the radiant heat flux in comparison with the average temperature profile, reaching to approximately 20% for the profile with 30% of turbulence intensity.