Abstract A numerical analysis of fluid-body interaction is performed in this work in order to evaluate the influence of vortex and tornado-like flows on immersed objects. Velocity profile models are adopted to generate vortical flow fields based on time-dependent boundary conditions and a finite element formulation is used for spatial discretization, where eight-node hexahedral elements with one-point integration are adopted. In addition, an arbitrary Lagrangian-Eulerian (ALE) approach is proposed to describe the relative motion between vortex flow and immersed objects. The flow governing equations are discretized using an explicit two-step Taylor-Galerkin scheme and tornado flow fields are simulated using the Rankine Combined Vortex Model (RCVM) and the Vatistas Model. Turbulence modeling is performed using Large Eddy Simulation (LES) with the Smagorinsky’s sub-grid scale model. Problems involving moving and stationary tornadoes interacting with fixed and moving objects are analyzed, where significant aerodynamic forces are observed on the immersed bodies, producing also significant changes in the vortex flow characteristics. fluidbody fluid body tornadolike like timedependent time dependent discretization eightnode eight node onepoint one point addition LagrangianEulerian Lagrangian Eulerian ALE (ALE twostep two step TaylorGalerkin Taylor Galerkin RCVM (RCVM LES (LES Smagorinskys Smagorinsky s subgrid sub grid model analyzed bodies characteristics

Abstract In the present work the performance of finite element formulations with different reduced integration strategies is evaluated for Contact Mechanics applications. One-point quadrature and selective reduced integration are utilized here using hourglass control to suppress volumetric and shear locking for materials with incompressible plastic behavior and bending-dominated problems. A corotational formulation is adopted to deal with physically and geometrically nonlinear analysis and the generalized-α method is employed for time integration in the nonlinear dynamic range. The contact formulation is based on the penalty method, where the classical Coulomb’s law is used considering a convected coordinate system for three-dimensional friction with large deformation and finite sliding. Contact problems involving deformable and rigid bodies, as well as static and dynamic analysis, are investigated and results are analyzed considering the different underintegration formulations proposed here.

Abstract A numerical investigation is performed here using a NURBS-based finite element formulation applied to classical Computational Fluid Dynamics (CFD) and Fluid-Structure Interaction (FSI) problems. Model capabilities related to refinement techniques are analyzed using a finite element formulation with NURBS (non uniform rational B-splines) basis functions, where B-splines and low-order Lagrangian elements can be considered as particular cases. An explicit two-step Taylor-Galerkin model is utilized for discretization of the fundamental flow equations and turbulence is considered using Large Eddy Simulation (LES) and the Smagorinsky’s sub-grid scale model. FSI is considered using an ALE kinematic formulation and a conservative partitioned coupling scheme with rigid body approach for large rotations is adopted. CFD and FSI applications are analyzed to evaluate the accuracy associated with the different refinement procedures utilized. Results show that high order basis functions with appropriate refinement and non-uniform parameterization lead to better predictions, compared with low-order Lagrangian models.

Abstract A finite element model for structural analysis of media with embedded inclusions is presented. The “embedded element concept” is adopted to model the contact interaction of two medium components along the contact interface considering a mixed 3D-1D formulation. The Mohr-Coulomb interface model is employed to define the bond-stress and bond-slip relation and strains associated with bond-slip are assumed to remain infinitesimal along the interface. Nonlinear analysis is performed with a corotational kinematics description introduced in the context of embedded approach. The problem of load transfer in mooring anchor systems was investigated and reasonable results were obtained using the present model.

Abstract A numerical investigation is performed in this work in order to evaluate the aerodynamic performance of building cross-section configurations by using corner modifications. The CAARC tall building model is utilized here as reference geometry, which is reshaped considering chamfered and recessed corners. The numerical scheme adopted in this work is presented and simulations are carried-out to obtain the wind loads on the building structures by means of aerodynamic coefficients as well as the flow field conditions near the model’s location. The explicit two-step Taylor-Galerkin scheme is employed in the context of the finite element method, where eight-node hexahedral finite elements with one-point quadrature are used for spatial discretization. Turbulence is described using the LES methodology, with a dynamic sub-grid scale model. Predictions obtained here are compared with experimental and numerical investigations performed previously. Results show that the use of corner modifications can reduce significantly the aerodynamic forces on the building structures, improve flow conditions near the building locations and increase the Strouhal number, which may have an important influence on aeroelastic effects.

A doença renal isquêmica ou nefropatia isquêmica relacionada à doença renovascular pode evoluir de forma rápida e progressiva para a insuficiência renal crônica. É fundamental a identificação e o tratamento precoces desta condição clínica, prevenindo a ocorrência de doença renal em estágio terminal, com consequente necessidade de terapia de substituição renal. Há uma década, o controle da hipertensão renovascular era o objetivo primário no manejo de pacientes com doença renovascular. Atualmente, a meta está dirigida principalmente para a estabilização e a melhora da função renal, além do controle dos níveis pressóricos.

Ischemic renal disease or ischemic nephropathy related to renovascular disease can progress rapidly and gradually to chronic renal failure. Early diagnosis and treatment is crucial for this clinical condition, because they can prevent occurrence of end-stage renal disease, with consequent need for renal replacement therapy. A decade ago, renovascular hypertension control was the primary objective in the management of patients with renovascular disease. Currently, the goal is addressed primarily to the stabilization and improvement of renal function, in addition to blood pressure control.