The Experts below are selected from a list of 1869 Experts worldwide ranked by ideXlab platform
Guilherme Rodrigues - One of the best experts on this subject based on the ideXlab platform.
-
Fração de vazio e gradiente de pressão nos escoamentos estratificados e anulares horizontais
2014Co-Authors: Guilherme RodriguesAbstract:Resumo: Neste trabalho, foram desenvolvidos dois modelos para predição de fração de vazio e gradiente de pressão em escoamentos horizontais com misturas bifásicas, nos padrões estratificado e anular. Um modelo considera o escoamento do filme líquido no regime laminar e o outro o considera turbulento. Os modelos desenvolvidos utilizam a idéia de tratamento diferencial para o filme líquido, como sugerido por Cheremisinoff & Davis [1979] e as equações constitutivas para fator de atrito interfacial e fração do perímetro molhado, propostos por Hart et alli. [1987]. Foi introduzido o conceito de "Número de Froude da Interface", para explicar a distribuição circunferencial do filme. As transições entre padrões de fluxo foram consideradas graduais. Os resultados dos modelos foram comparados com dados experimentais . próprios, realizados no laboratório do CENPES, e resultados publicados na literaturaAbstract: The prediction of void fraction and pressure gradient in a horizontal two-phase separated flow is the main goal in this work. The flow regimes covered were the stratified-smooth, the stratified-wavy and the annular flow. A differential approach was adopted to solve the flow in the liquid film, with a velocity profile resulting from the imposed boundary conditions. Two models were developed, considering the film beeing either in the laminar or turbulent flow condition. The liquid film distribution in the circunferential direction was considered and the correlation proposed by Hart et alii [1987] was adopted to calculate the wetted perimeter. Thus, the liquid was considered to be flowing in a channel of constant height. The gas flow was solved by means of an integral approach. Experimental void fraction and pressure drop data were taken in a set-up built in the Multiphase Flow Testing Plant site, at CENPES/PETROBRAS. The predictions of the theory are in satisfactory agreement wjth experimental data. Results from models published in the literature, as well as other experimental data were also used for, comparison. It is shown that the interfacial Froude number, based on the interfadal shear stress establishes the application range for the model, with errors less than ?mais ou menos? 5
-
Fração de vazio e gradiente de pressão nos escoamentos estratificados e anulares horizontais
Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica e Instituto de Geociências, 1991Co-Authors: Guilherme RodriguesAbstract:Neste trabalho, foram desenvolvidos dois modelos para predição de fração de vazio e gradiente de pressão em escoamentos horizontais com misturas bifásicas, nos padrões estratificado e anular. Um modelo considera o escoamento do filme líquido no regime laminar e o outro o considera turbulento. Os modelos desenvolvidos utilizam a idéia de tratamento diferencial para o filme líquido, como sugerido por Cheremisinoff & Davis [1979] e as equações constitutivas para fator de atrito interfacial e fração do perímetro molhado, propostos por Hart et alli. [1987]. Foi introduzido o conceito de "Número de Froude da Interface", para explicar a distribuição circunferencial do filme. As transições entre padrões de fluxo foram consideradas graduais. Os resultados dos modelos foram comparados com dados experimentais . próprios, realizados no laboratório do CENPES, e resultados publicados na literaturaThe prediction of void fraction and pressure gradient in a horizontal two-phase separated flow is the main goal in this work. The flow regimes covered were the stratified-smooth, the stratified-wavy and the annular flow. A differential approach was adopted to solve the flow in the liquid film, with a velocity profile resulting from the imposed boundary conditions. Two models were developed, considering the film beeing either in the laminar or turbulent flow condition. The liquid film distribution in the circunferential direction was considered and the correlation proposed by Hart et alii [1987] was adopted to calculate the wetted perimeter. Thus, the liquid was considered to be flowing in a channel of constant height. The gas flow was solved by means of an integral approach. Experimental void fraction and pressure drop data were taken in a set-up built in the Multiphase Flow Testing Plant site, at CENPES/PETROBRAS. The predictions of the theory are in satisfactory agreement wjth experimental data. Results from models published in the literature, as well as other experimental data were also used for, comparison. It is shown that the interfacial Froude number, based on the interfadal shear stress establishes the application range for the model, with errors less than ?mais ou menos? 5
Rodrigues Junior Guilherme - One of the best experts on this subject based on the ideXlab platform.
-
Fração de vazio e gradiente de pressão nos escoamentos estratificados e anulares horizontais
[s.n.], 2018Co-Authors: Rodrigues Junior GuilhermeAbstract:Orientador: Fernando de Almeida FrançaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia MecanicaResumo: Neste trabalho, foram desenvolvidos dois modelos para predição de fração de vazio e gradiente de pressão em escoamentos horizontais com misturas bifásicas, nos padrões estratificado e anular. Um modelo considera o escoamento do filme líquido no regime laminar e o outro o considera turbulento. Os modelos desenvolvidos utilizam a idéia de tratamento diferencial para o filme líquido, como sugerido por Cheremisinoff & Davis [1979] e as equações constitutivas para fator de atrito interfacial e fração do perímetro molhado, propostos por Hart et alli. [1987]. Foi introduzido o conceito de "Número de Froude da Interface", para explicar a distribuição circunferencial do filme. As transições entre padrões de fluxo foram consideradas graduais. Os resultados dos modelos foram comparados com dados experimentais . próprios, realizados no laboratório do CENPES, e resultados publicados na literaturaAbstract: The prediction of void fraction and pressure gradient in a horizontal two-phase separated flow is the main goal in this work. The flow regimes covered were the stratified-smooth, the stratified-wavy and the annular flow. A differential approach was adopted to solve the flow in the liquid film, with a velocity profile resulting from the imposed boundary conditions. Two models were developed, considering the film beeing either in the laminar or turbulent flow condition. The liquid film distribution in the circunferential direction was considered and the correlation proposed by Hart et alii [1987] was adopted to calculate the wetted perimeter. Thus, the liquid was considered to be flowing in a channel of constant height. The gas flow was solved by means of an integral approach. Experimental void fraction and pressure drop data were taken in a set-up built in the Multiphase Flow Testing Plant site, at CENPES/PETROBRAS. The predictions of the theory are in satisfactory agreement wjth experimental data. Results from models published in the literature, as well as other experimental data were also used for, comparison. It is shown that the interfacial Froude number, based on the interfadal shear stress establishes the application range for the model, with errors less than 'mais ou menos' 5 %MestradoMestre em Engenharia de Petróle
Celso Edmundo Bochetti Foelkel - One of the best experts on this subject based on the ideXlab platform.
-
METODOLOGIA ALTERNATIVA PARA O TRATAMENTO DE EFLUENTES DE INDÚSTRIA DE CELULOSE KRAFT ALTERNATIVE METHODOLOGY FOR TREATMENT OF THE EFFLUENTS FROM THE CELULOSE KRAFT INDUSTRY
1994Co-Authors: Sonia Maria Bitencourt Frizzo, Maria Cladis Mezzomo Da Silva, Ayrton Figueredo Martins, Celso Edmundo Bochetti FoelkelAbstract:SUMMARY Procedures based on the reuse of solid residues and the surplus of process chemicals for the tertiary treatment process of the Riocell S.A. (Guaiba, RS. - Brazil), are described. The effluent samples were characterized in relation to their color and content of organ-halogenated compounds and then submitted to a conditioning step with the application of two different flocculants using solid residues of process ("dreg", " grit", ashes) and active carbon as coadjuvants. An appreciable reduction of the color and content in organ-halogenated compounds was observed, as well as a economy on costs with flocculants. Key words: chemicals process, effluent, celulose. INTRODUCAO A possibilidade de utilizacao de residuos solidos ("dreg","grit" e cinzas), no tratamento de efluentes, e, de excedente (cloro), na producao de cloreto ferrico, ambos subprodutos da linha de producao, constitui uma elegante alternativa para o reaproveitamento de residuos. O uso de carvao ativado como coadjuvante de floculacao, ademais, complementa estudos preliminares (AWWA, 1974, Cheremisinoff & MORRESI, 1980, FROEHLICH, 1987 e GRULICH
R. Kouhikamali - One of the best experts on this subject based on the ideXlab platform.
-
Numerical investigation of the minimum fluidization velocity in a gas–solid fluidized bed using discrete phase model
Journal of the Brazilian Society of Mechanical Sciences and Engineering, 2018Co-Authors: M. Mehdizad, R. KouhikamaliAbstract:The main purpose of this work is to find a new numerical model that is capable of investigating the minimum fluidization velocity in a gas–solid bed over a broad range of particle diameters and particle densities. In the present work, CFD simulation of a cylindrical gas–solid fluidized bed has been carried out using discrete phase model. Different drag correlations were examined to simulate the momentum between phases. Comparing the numerical values with the experimental values of the minimum fluidization velocity indicates that the drag models of Cheremisinoff and Gupta and Holzer and Sommerfeld have the least deviation, so they are suitable for modeling the drag forces of spherical and non-spherical particles, respectively. Experimental studies were carried out using a 10.5 cm cylindrical bed. The ranges of particles diameter and density vary from 10 μm to 10 mm and 6–6500 kg/m^3, respectively. Results showed that by 25% enhancement in diameter, density, crosswise sphericity coefficient, and sphericity of particles, the minimum fluidization velocity increases 94, 27, 12.5, and 3.5%, respectively. The numerical results of both spherical and non-spherical particles are in a very good agreement with experimental data within an average error of 6 and 9%, respectively.
Sonia Maria Bitencourt Frizzo - One of the best experts on this subject based on the ideXlab platform.
-
METODOLOGIA ALTERNATIVA PARA O TRATAMENTO DE EFLUENTES DE INDÚSTRIA DE CELULOSE KRAFT ALTERNATIVE METHODOLOGY FOR TREATMENT OF THE EFFLUENTS FROM THE CELULOSE KRAFT INDUSTRY
1994Co-Authors: Sonia Maria Bitencourt Frizzo, Maria Cladis Mezzomo Da Silva, Ayrton Figueredo Martins, Celso Edmundo Bochetti FoelkelAbstract:SUMMARY Procedures based on the reuse of solid residues and the surplus of process chemicals for the tertiary treatment process of the Riocell S.A. (Guaiba, RS. - Brazil), are described. The effluent samples were characterized in relation to their color and content of organ-halogenated compounds and then submitted to a conditioning step with the application of two different flocculants using solid residues of process ("dreg", " grit", ashes) and active carbon as coadjuvants. An appreciable reduction of the color and content in organ-halogenated compounds was observed, as well as a economy on costs with flocculants. Key words: chemicals process, effluent, celulose. INTRODUCAO A possibilidade de utilizacao de residuos solidos ("dreg","grit" e cinzas), no tratamento de efluentes, e, de excedente (cloro), na producao de cloreto ferrico, ambos subprodutos da linha de producao, constitui uma elegante alternativa para o reaproveitamento de residuos. O uso de carvao ativado como coadjuvante de floculacao, ademais, complementa estudos preliminares (AWWA, 1974, Cheremisinoff & MORRESI, 1980, FROEHLICH, 1987 e GRULICH