Viscous-inviscid iteration is a technique for the analysis of fl ows that although not being as p... more Viscous-inviscid iteration is a technique for the analysis of fl ows that although not being as precise as a complete Navier-Stokes solution allows very small computational times and that makes it an ideal tool for preliminary or optimization studies. This work reports the c oupling o f an Euler s olver with a d ifferential boundary layer code, using the Cebeci-Smith turbulence model. Results are presented for the RAE 2822 airfoil in transonic and in subsonic flow with a high angle of attack. The results show that the coupling methodology is adequate and that convergence was obtained in critical conditions like the presence of shocks and separation. In the transonic flow, there is s ome disagreement with the experimental results for the pressure coeficient, previously published work indicate that this is probably due to the use of a coarse mesh. The importance of computational fluid dynamics (CFD) as a tool for the study of aerodynamic shapes has grown steadily in the last decades. ...
Traditionally, reduced physical models are used to allow control, instrumentation and experimenta... more Traditionally, reduced physical models are used to allow control, instrumentation and experimental evaluation of flow. More recently, computational fluid dynamics (CFD) has emerged as a tool that allows numerical modeling of flows and can complement the information provided by the physical model. The objective this paper is to validate the CFD tool in reproducing the flow through an ogee crest spillway with a roller bucket stilling basin. This validation was performed with the data from a reduced scale experiment in which measurements were made of the position of the water free surface and of the pressure loads in the spillway profile. It was verified that the CFD tool is suitable for the study of this type of flow, being able to reproduce the experimental results. In the execution of the numerical simulations, special attention was given to the influence of the mesh on the results. An important influence of the mesh was observed in some results, which shows the importance a sensiti...
Valves are widely used in several areas, and their application in building installations is commo... more Valves are widely used in several areas, and their application in building installations is common, e.g., as shower control valves. Rapid technological advances have resulted in improvements to valve performance, reducing water and energy consumption. Removing parts external to the masonry improves space use and ergonomics in valve operation. Front access to the internal parts of a valve facilitates maintenance. The objective of this study is to present a new model of hydraulic valve for building installations, designed to decrease head loss, increase controllability, and eliminate parts outside the masonry. Three geometries were initially designed using SolidWorks, and a CFD model was used to specify the pressures at the inlet and outlet of the analyzed sections. As a result, the third valve geometry presented a pressure drop coefficient when 100% open that was roughly one third of that typically seen in globe valves. The pumps and the reduction in head loss implied that lower powe...
The aim of this work is to discuss the effect of urban block and lot design in natural ventilatio... more The aim of this work is to discuss the effect of urban block and lot design in natural ventilation of selfbuilt houses in the city of Campinas, Brazil. The research was carried out with CFD simulation, using the software PHOENICS to calculate air velocities in the external regions of the residences. The case study was a surrounding in the city, the settlement São José, which was urbanized by the public organs having in mind low-income self-builders. The houses were analyzed through results of two surveys: one in the years ...
Viscous-inviscid iteration is a technique for the analysis of fl ows that although not being as p... more Viscous-inviscid iteration is a technique for the analysis of fl ows that although not being as precise as a complete Navier-Stokes solution allows very small computational times and that makes it an ideal tool for preliminary or optimization studies. This work reports the c oupling o f an Euler s olver with a d ifferential boundary layer code, using the Cebeci-Smith turbulence model. Results are presented for the RAE 2822 airfoil in transonic and in subsonic flow with a high angle of attack. The results show that the coupling methodology is adequate and that convergence was obtained in critical conditions like the presence of shocks and separation. In the transonic flow, there is s ome disagreement with the experimental results for the pressure coeficient, previously published work indicate that this is probably due to the use of a coarse mesh. The importance of computational fluid dynamics (CFD) as a tool for the study of aerodynamic shapes has grown steadily in the last decades. ...
Traditionally, reduced physical models are used to allow control, instrumentation and experimenta... more Traditionally, reduced physical models are used to allow control, instrumentation and experimental evaluation of flow. More recently, computational fluid dynamics (CFD) has emerged as a tool that allows numerical modeling of flows and can complement the information provided by the physical model. The objective this paper is to validate the CFD tool in reproducing the flow through an ogee crest spillway with a roller bucket stilling basin. This validation was performed with the data from a reduced scale experiment in which measurements were made of the position of the water free surface and of the pressure loads in the spillway profile. It was verified that the CFD tool is suitable for the study of this type of flow, being able to reproduce the experimental results. In the execution of the numerical simulations, special attention was given to the influence of the mesh on the results. An important influence of the mesh was observed in some results, which shows the importance a sensiti...
Valves are widely used in several areas, and their application in building installations is commo... more Valves are widely used in several areas, and their application in building installations is common, e.g., as shower control valves. Rapid technological advances have resulted in improvements to valve performance, reducing water and energy consumption. Removing parts external to the masonry improves space use and ergonomics in valve operation. Front access to the internal parts of a valve facilitates maintenance. The objective of this study is to present a new model of hydraulic valve for building installations, designed to decrease head loss, increase controllability, and eliminate parts outside the masonry. Three geometries were initially designed using SolidWorks, and a CFD model was used to specify the pressures at the inlet and outlet of the analyzed sections. As a result, the third valve geometry presented a pressure drop coefficient when 100% open that was roughly one third of that typically seen in globe valves. The pumps and the reduction in head loss implied that lower powe...
The aim of this work is to discuss the effect of urban block and lot design in natural ventilatio... more The aim of this work is to discuss the effect of urban block and lot design in natural ventilation of selfbuilt houses in the city of Campinas, Brazil. The research was carried out with CFD simulation, using the software PHOENICS to calculate air velocities in the external regions of the residences. The case study was a surrounding in the city, the settlement São José, which was urbanized by the public organs having in mind low-income self-builders. The houses were analyzed through results of two surveys: one in the years ...
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