EE - Trabalhos apresentados em eventos
URI permanente para esta coleçãohttps://rihomolog.furg.br/handle/1/515
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Resultados da Pesquisa
- ItemApplication of the computational modeling in the resin transfer molding (RTM) process: a case study of a marine propeller(2012) Porto, Joseane da Silva; Letzow, Max; Santos, Elizaldo Domingues dos; Souza, Jeferson Avila; Isoldi, Liércio André; Amico, Sandro CamposThis work presents one example of how the computational modeling can help in the Resin Transfer Molding (RTM) process when it is applied to the production of parts with complex geometry, such as the marine propellers. This manufacture process of composite material parts consists in the injection of a polymeric resin into a closed mold where a fibrous reinforcement is previously placed. The numerical simulation of the RTM process can be considered as the resin flow through a porous media. This computational model was developed in the FLUENT package, which is based on the Finite Volume Method (FVM), and was applied to study a propeller for naval propulsion. As the propeller has a complex format, the use of computational approach as a preliminar step in the manufacturing process is very important for the correct definition of the inlet and outlet nozzles. So, it is possible to design an efficient mold, avoinding extras costs related with the mold redesign, the resin waste and the increase of injection time. The results showed that an inadequate positioning of the mold outlet nozzles causes an increase about 10% and 2% in the production time and in the resin amount, respectively, for obtaining the marine propeller by RTM process.
- ItemNumerical analysis of a regular wave over a vertical pile with a square section(2010) Teixeira, Paulo Roberto de Freitas; Gomes, Mateus das Neves; Santos, Elizaldo Domingues dos; Isoldi, Liércio André; Rocha, Luiz Alberto OliveiraThe study of the action of waves on piles is very important for the design of structures in coastal and oceanic areas. Currently, there is strong interest in analyzing the action of waves on piles with non-circular sections, such as rectangular or square ones. According to Vengatesan et al. (2000), the main reason for this interest is the low cost of the connections of the members in the structures with these sections. The objective of this paper is to analyze the action of a regular wave on a vertical pile with a square section employing two differents numerical methodologies for prediction of the wave fluid dynamic. To achieve this goal were used the FLUINCO and FLUENT® softwares. FLUINCO (Teixeira, 2001) employs a partitioned two-step semi-implicit Taylor-Galerkin method in the Navier-Stokes equations. The free surface is governed by its kinematic boundary condition and an arbitrary Lagrangian-Eulerian (ALE) formulation is used to enable movements of the free surface. The FLUENT® code (2006), version 6.3.26, implements a finite volume technique to solve the equation of continuity and the Navier-Stokes equations. The free surface is described by using the VOF method (Volume Of Fluid). The wave period of the studied problem is 4s and its height is 0.05 m. The pile is seated on the bottom and located in the center of a channel. The dimensions of the pile section are 1m × 1m and the channel is 30m long, 10m wide and 1m deep. This paper shows the results obtained by the models in terms of the velocity vectors, the deformation of the free surface and the drag force caused by the wave on the pile. The total horizontal force acting on the pile was analytically calculated using the Morison equation. It was observed very similar results to the numerical ones.
- ItemEstudo numérico de uma placa submersa vista como quebra-mar e conversor de energia das ondas(2012) Seibt, Flávio Medeiros; Couto, Eduardo Costa; Teixeira, Paulo Roberto de Freitas; Santos, Elizaldo Domingues dos; Isoldi, Liércio AndréA crescente pesquisa por fontes de energia limpa e renovável tem contribuído para dar relevância ao estudo da energia das ondas do mar. Este artigo apresenta um modelo computacional desenvolvido para analisar o dispositivo placa submersa utilizado como quebra-mar e como conversor de energia das ondas do mar em energia elétrica. A dupla função deste dispositivo o distingue dos demais conversores de energia das ondas. O modelo desenvolvido utiliza os códigos comerciais GAMBIT e FLUENT. Neste último, a metodologia usada para representar a interação ar-água nas simulações numéricas do dispositivo é a multifásica Volume de Fluido. O objetivo deste artigo é contribuir para um maior conhecimento deste dispositivo analisando a influência do comprimento da placa no seu desempenho nas duas funções. Para tanto, o modelo desenvolvido, depois de validado, é aplicado em cinco simulações que se distinguem apenas pelo comprimento da placa. Nestas simulações, o seu desempenho na função de quebra-mar é quantificado por meio do coeficiente de transmissão. Já, o seu desempenho como conversor de energia é avaliado por sua eficiência em captar a energia das ondas incidentes. Constata-se que para um comprimento de placa, adimensionalizado pelo comprimento da onda, inferior à 0.83, as funções quebra-mar e conversor de energia não são concorrentes.