Oliveira C.P.,Programa de Pos Graduacao em Modelagem Computacional PPGMC |
Souza J.A.,Programa de Pos Graduacao em Modelagem Computacional PPGMC |
Souza J.A.,Grande Rio University |
Isoldi L.A.,Programa de Pos Graduacao em Modelagem Computacional PPGMC |
And 2 more authors.
Journal of Reinforced Plastics and Composites | Year: 2013
An analytical model for the multilayer rectilinear injection applied to the RTM process has been developed. The model takes into account the permeability in both in-plane (Kxx and Kyy) and transverse (Kzz) directions of each layer of the reinforcement media and calculates the transverse permeability (Kt) through adjacent layers. Porosity and thickness are set independent for each layer of the assembly. Mass balance of resin within the layers is used to develop an expression that estimates resin position (xi) as a function of time (t) independently of each layer. The resulting equation was solved using: (i) Numerical integration and (ii) algebraic integration of the simplified expression resulting in a closed expression for xi-=-xi(t). Results of both proposed methods were compared with the calculations performed using the PAM-RTM software for cases with three, five and seven layers and the maximum calculated error in all cases was less than 12%. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Vaz J.,Federal University of Rio Grande do Sul |
Sattler M.A.,Federal University of Rio Grande do Sul |
Brum R.D.S.,Programa de Pos Graduacao em Modelagem Computacional PPGMC |
Brum R.D.S.,Federal University of Rio Grande do Sul
Energy and Buildings | Year: 2014
The thermal potential of Earth-Air Heat Exchangers (EAHE) is experimentally investigated for a placement in Viamão, city located in the south of Brazil. Three independent ducts are buried in the soil, ducts A and B are installed at a depth of 1.60 m and 0.60 m apart, while duct C is installed at a depth of 0.50 m. The thermal conditions of one build named Casa Ventura are improved with the EAHE. The temperatures for the soil, external air and in buried ducts in several positions are acquired along one year (2007). The main purpose here is the achievement of the transient behavior of temperature fields for the external air, soil and buried ducts and the best periods of time for employment of device. Results showed that the months of May and February were the best for heating and cooling the air used in Casa Ventura, respectively. Moreover, it was developed a complete database about the transient temperatures of the soil, external air and inside the building. © 2013 Elsevier B.V.