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COB232 ANÁLISE E SIMULAÇÃO DE UMA TURBINA REGENERATIVA TIPO TOROIDAL / ANALYSIS AND SIMULATION OF A REGENERATIVE TOROIDAL TURBINE
José Edmar Rios(*), Sebastião Varella(**) & Nelson Manzanares Filho(**)
(*)Departamento de Física Aplicada - FUNREI - Praça Frei Orlando, 170,
CEP 36300-000 São João del-Rei MG, Brasil - E-mail: dfiap@csa.funrei.br.
(**)Departamento de Engenharia Mecânica - EFEI - Av. B.P.S., 1303
CEP 37500-000 Itajubá MG, Brasil - E-mail: nelson@iem.efei.rmg.br
An analysis and a simulation of a regenerative toroidal turbomachine are made in order to evaluate its potentiality as hydraulic turbine. The working principle of this kind of turbomachine is presented and discussed. Formulae developed on the basis of the circulatory theory are presented allowing the calculation of the circulatory velocity and the global pressure coefficient as a function of the main geometric parameters. Based on these formulae, simulation results were obtained for the variation of the flow rate vs. rotating speed with a fixed specific energy and taking the diameter aspect ratio as a parameter. The operating characteristic is similar to that of a Francis turbine of high specific speed. In order to check the simulation model, some experimental results were obtained by means of rig tests performed on an hydraulic regenerative turbine. One verifies that the simulation model is capable of qualitatively reproducing the flow rate vs. rotating speed curve. One concludes in favor of the applicability of the regenerative turbomachine as hydraulic turbine and suggests that new researches have to be made for further evaluations and improvements.
Keywords: Hydraulic Turbine; Regenerative; Toroidal. / Turbina Hidráulica; Regenerativa: Toroidal.
COB274 SIMULAÇÃO DO ESCOAMENTO ENTRE PÁS DE UMA TURBOMÁQUINA COMO METODOLOGIA DE PROJETO / FLOW SIMULATION INSIDE A BLADE PASSAGE OF A TURBOMACHINE AS A DESIGN METHODOLOGY
Vilson C. S. Ferreira, Inácio B. Morsch, Martin P. Kessler & Carlos F. Favaretto
Laboratório de Turbomáquinas e Medição de Fluxo - DEMEC - UFRGS
Sarmento Leite 425, Porto Alegre, CEP. 90050 - 170 - E-mail: morsch@vortex.ufrgs.br
Many theoretical and experimental approaches have been made in order to achieve a standard and reliable turbomachinery design. The present paper describes an underdevelopment methodology that links an initial design software with commercial computational package (CFD) available. The geometry of a turbomachine is generated by the initial software and, after the visualisation, the data are exported to the CFD which solves the flow field inside the blade-to-blade passage. A simulation with a submergible pump impeller is made and the results in terms of velocity, pressure and streamlines distribution are presented.
Keywords: Turbomáquinas, escoamento, turbulência, simulação numérica, desenvolvimento de projeto. Turbomachine, flow, turbulence, numerical simulation, design improvement.
COB751 USO DE APLICATIVOS COMPUTACIONAIS NA MANUFATURA DE COMPONENTES DE BOMBAS CENTRÍFUGAS / COMPUTER APPLICATIONS IN CENTRIFUGAL PUMPS MANUFACTURING
Sergio Kenji Moriguchi & Douglas Lauria
Departamento de Engenharia Mecânica, Escola de Engenharia Mauá, Escola Politécnica da
USP - Estrada das Lágrimas, 2035 Cep 09580-900 S. C. do Sul - SP
This paper deals with the use of hardware and software computational features and periphericals in an integrated form to design centrifugal pumps. Results of the impeller and spiral casing basic dimensions are determined as design parameters and corresponding drawings files are generated. Computer Aided Engineering technique is used in the equipment data files. The design information expressed in neutral and parametric form enables the direct use of aplication softwares. This way, is possible to check and print out drawings and execute components machining. At the work cycle end the use of the computer allows to dimension and manufacture the pump components reducing manufacturing time and costs.
Keywords: Rotores de bombas centrifugas, Caixa espiral, Bombas centrifugas, CAD, CAM / Centrifugal pumps, Spiral casing, Impeller, CAD, CAM.
COB888 AN UNSTEADY NUMERICAL SIMULATION OF NA OSCILLATING AIRFOIL WITH STRUCTURAL COUPLING
Saïd Mounsif
Grupo de Turbomáquinas, Departamento de Engenharia Mecânica, CT - UFPA
CEP 66.075-900 Belém, Pará, Brasil - E-mail: gtdem@amazon.com.br
Unsteady flow-fields of two-dimensional oscillating airfoil with structural coupling are calculated using an implicit finite-volume numerical procedure. The method employs the semi-strong conservation form of the Navier-Stokes equations with pressure and physical contravarient velocity components as dependent variables. The equations describing the airfoil motion are integrated in time using a fourth-order Runge-Kutta algorithm. Numerical experiments are performed about an unsteady viscous flow-filed past a stay-vane airfoil, which is free to vibrate in response to the aerodynamic forces.
Keywords: Fluid-Structure Interaction, Finite-Volume Method, Moving Curvilinear Coordinates.
COB1217 DEVELOPMENT AND TESTING OF A SMALL DARRIEUS-TYPE TURBINE IN TIDAL CURRENTS NEAR THE MOUTH OF THE AMAZON
Danielle R. S. Guerra, André L. Amarante Mesquita & Scott D. Anderson*
Grupo de Turbomáquinas, Depto. de Engenharia Mecânica, Universidade Federal do Pará, 66075-900 Belém-PA-Brasil
E-mail: gtdem@amazon.com.br
*Goeldi Museum, Caixa Postal 893, 66.017-970 Belém, Pará, Brazil
Parts of the northern region of Brazil face serious problems with the supply of electric energy. Thousands of residents near the mouth of the Amazon live dispersed on forest-covered flood plains cut by wide rivers and streams. Thus, for them it is necessary that the electric energy be generated on a small-scale, in a decentralized manner, and at low cost. In this context, this paper presents a experimental study on the performance of a Darrieus-type water turbine. The experiments were carried out in situ and the results are consistent with the experimental data available in the literature.
Keywords: Darrieus runner, tide-energy, electric power
COB1404 ANÁLISE DO ESCOAMENTO IDEAL EM GRADES REGENERATIVAS TOROIDAIS COM EFEITOS NÃO-INERCIAIS / ANALYSIS OF THE IDEAL FLOW IN REGENERATIVE TOROIDAL CASCADES INCLUDING NON-INERTIAL EFFECTS
Ramiro G. Ramirez Camacho, Nelson Manzanares Filho & Sebastião Varella
Departamento de Engenharia Mecânica - EFEI - Av. B.P.S., 1303, CEP 37500-000 Itajubá MG, Brasil - E-mail: nelson@iem.efei.rmg.br
An ideal rotational flow model for regenerative toroidal cascades with thin blades including non-inertial effects is presented. A conformal mapping is applied in order to transform the toroidal cascade surface in a plane cascade. Vortex distributions are employed to simulate the blade perturbation in the transformed plane. The vortex intensity is calculated by numerically solving an integral equation representative of the relative flow tangency on the blades. The resultant blade circulation is related to the absolute vorticity on the physical toroidal surface. This vorticity creates the circunferencial pressure gradient of a regenerative turbomachine and this fact motivates the present research. Illustrative results for the vorticity and the slip factor are presented as a function of the main geometric parameters of the toroidal cascade.
Keywords: regenerative cascades; toroidal surfaces; non-inertial effects; vorticity. / grades regenerativas; superfícies toroidais; efeitos não-inerciais; vorticidade.
COB1444 ANÁLISE DE CAMADA LIMITE TURBULENTA TRIDIMENSIONAL EM PÁS DE TURBINAS HIDRÁULICAS / TRIDIMENSIONAL TURBULENT BOUNDARY LAYER ANALYSIS ON HYDRAULIC TURBINE ROTOR BLADES
Marcos David Bloch* & José Carlos Cesar Amorim¤
*Pós-Graduação em Engenharia Mecânica, Departamento de Energia, FEG – UNESP – Guaratinguetá
12500-000 Guaratinguetá, SP, Brasil – E-mail: mbloch@feg.unesp.br
¤IME – Instituto Militar de Engenharia, Praia Vermelha, 22290-270 Rio de Janeiro, RJ, Brasil – E-mail: jcamorim@ime.eb.br
A numerical analysis has been developed for calculating viscous flows over arbitrary surfaces by solving the tridimensional turbulent boundary-layer equations. The governing equations are written in a general nonorthogonal coordinate system. The inviscid properties are obtained from the surface Euler equations. A simple algebraic model for Reynolds turbulent stresses is used to close the set of equations. The resulting equations are discretized and approximated by a two-point finite-difference numerical scheme. The procedure developed in this paper is validated for some standard test cases and applied for turbine rotor blades.
Keywords: camada limite/boundary layer; análise numérica/numerical method; escoamento turbulento 3-D/3-D turbulent flow; diferenças-finitas/finite difference, turbomáquinas/turbomachinery.
COB1485 ANÁLISE DOS ESFORÇOS HIDRODINÂMICOS EM COMPORTAS HIDRÁULICAS / NUMERICAL ANALYSIS OF HYDRODYNAMIC FORCES ACTING ON VERTICAL LIFT GATES
Jell Lima de Andrade* & José Carlos Cesar Amorim¤
*Mecânica Pesada S.A., Grupo GEC-ALSTHOM / Pós-Graduação em Engenharia Mecânica, FEG - UNESP
12040-001 Taubaté, SP, Brasil
¤IME – Instituto Militar de Engenharia, Praia Vermelha, 22290-270 Rio de Janeiro, RJ, Brasil – E-mail: jcamorim@ime.eb.br
A numerical analysis has been developed for calculating viscous flows controlled by a vertical lift gate and hydrodynamic forces acting on it. The numerical solution is obtained from the incompressible Navier-Stokes equations. The numerical technique is based on a finite element method. A Poisson equation is derived from the pressure-weighted substitution of the full momentum equations into the continuity equation. Turbulence effects are simulated by a k-e turbulence model. The procedure developed here is applied for a vertical lift gate operating in a CESP installation, and the results are compared with available experimental data at various opening positions. Good agreement is obtained for the velocity and pressure distributions.
Keywords: Análise numérica/numerical analysis; método dos elementos finitos/finite element method; escoamento turbulento/turbulent flow; comportas/lift gates; esforços hidrodinâmicos/hydrodynamic forces.
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