H.S. da Costa Mattos

Modeling of the Fluid-Structure Interaction in Inelastic Piping Systems

In many engineering applications, compliant piping systems conveying liquids are subjected to inelastic deformations due to severe pressure surges such as plastic tubes in modern water supply transmission lines and metallic pipings in nuclear power plants. In these cases the design of such systems may require an adequate modeling of the interactions between the fluid dynamics and the inelastic structural pipe motions. The reliability of the prediction of fluid-pipe behavior depends mainly on the adequacy of the constitutive equations employed in the analysis. In this paper it is proposed a systematic and general approach to consistently incorporate different kinds of inelastic behaviors of the pipe material in a fluid-structure interaction analysis. The main feature of the constitutive equations considered in this work is that a very simple numerical technique can be used for solving the coupled equations describing the dynamics of the fluid and pipe wall. Numerical examples concerning the analysis of polyethylene and stainless steel pipe networks are presented to illustrate the versatility of the proposed approach.

Influence of temperature on the bending stiffness and tensile-shear strength of composite-metal joints

ABSTRACT The temperature effect on bending and shear strength of single lap joints, composed by metal–composite substrates with fixed geometry, was evaluated in this paper. The tests provide analysis associated with a system frequently used in the oil and gas industry, characterized by the use of polymeric composite materials with adhesives for repairing and reinforcing pipelines. The results revealed that the tensile behavior of the composite is highly affected by temperature and can be predicted by a linear function with good agreement. The bending stiffness and tensile-shear strength of composite–metal single lap joints are also dependent of the test temperature. The first can be represented by a linear equation and the second by a power law, both with good agreement.