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The aim of the paper is to determine the most important features of damping in the case of an advanced sandwich composite structure starting from the dampings, dynamic Young moduli and Poisson ratio for every lamina. The structure features two carbon/epoxy skins reinforced with twill weave fabric and an expanded polystyrene (EPS) core. At the damping analysis of fibre reinforced composite materials, a so called concept of complex moduli will be used in which the elastic constants will be replaced through their viscoelastic correspondences. The mechanical modeling is based on the correspondence principle of linear viscoelastic theory. Testing scheme allows specimens to be put in one side fixed connection and subjected at bending oscillations in normal conditions: 23°C, 50% relative air humidity. Dampings, rigidities and compliances of the composite structure are computed. [ABSTRACT FROM AUTHOR]

Motived by the aim of modelling the behavior of swirling flow motion, we present a 1D hierarchical model for an Rivlin-Ericksen fluid with complexity n = 2 flowing in a circular straight tube with constant radius. Integrating the equation of conservation of linear momentum over the tube cross-section, with the velocity field approximated by the Cosserat theory, we obtain a one-dimensional system depending only on time and on a single spatial variable. The velocity field approximation satisfies both the incompressibility condition and the kinematic boundary condition exactly. From this new system, we derive the equation for the wall shear stress and the relationship between average pressure gradient, volume flow rate and swirling scalar function over a finite section of the tube. Also, we obtain the corresponding partial differential equation for the swirling scalar function. [ABSTRACT FROM AUTHOR]

The research for the complex properties of visco-elastic material in various impact conditions have been interesting and difficult problems, especially in the auto-crash safety engineering process. In this paper an application of boundary-layer computing for the non-Newtonian rate type impact hardening and share thinning phenomenon are discussed. The numerical scheme yields the convergent finite element analysis (FEA) solution and stable semi-discrete Galerkin-Runge-Kutta(G-RK) iteration. To develope the passive protection model based on the non-recover solid metal (phase1) impact, we are deepening our knowledge of soft material recover protection (phase2) concept. The high performance computing (HPC) tool enabled us to carry out the research on the passive safety analysis with engineering computing. [ABSTRACT FROM AUTHOR]

This paper presents the viscoelastic behaviour of skin tissue under different thermal loadings and discusses the effect of temperature and corresponding dermal collagen denaturation on the mechanical viscoelastic properties of skin tissue. Differential scanning calorimetry (DSC) has been used to detect dermal collagen denaturation and to assess its thermal stability. The DSC results under various heating rates are used to derive the Arrhenius parameters (Ea , A ) in the burn damage integration, which are then used to calculate the degree of denatured collagen in the skin. Temperature tests have been performed using a dynamic mechanical analyzer (DMA) to evaluate changes in the skin viscoelastic properties as a function of collagen damage, specifically, to assess the changes in the storage modulus (E'), and loss factor (tan λ). The results show remarkable changes in ' E , which is maybe due to the release of water, but there is no significant effect from tan λ. These results suggest that at a constant frequency the denaturation of collagen molecules has little effect on the viscoelasticity. [ABSTRACT FROM AUTHOR]