The inverse energy cascade of two-dimensional (2D) turbulence is often represented phenomenologically by a Newtonian stress-strain relation with a ‘negative eddy-viscosity’. Here we develop a fundamental approach to a turbulent constitutive law for the 2D inverse cascade, based upon a convergent multi-scale gradient (MSG) expansion. To first order in gradients we find that the turbulent stress ...

in a recent paper, de baets et al. have characterized the fuzzytolerance and fuzzy equivalence relations that a given strict order relation iscompatible with. in this paper, we generalize this characterization by consideringan arbitrary (crisp) relation instead of a strict order relation, while payingattention to the particular cases of a reflexive or irreflexive relation. the reasoninglargely ...

A new and powerful indentation hardness (H) approach to evaluating the true stress (σ)-true plastic strain (ε), σ(ε), constitutive behavior of materials is described. Since measurements of H intrinsically probe a wide-range of ε (up to ≈0.5) , accurate assessment of the corresponding yield (σy) stress and strain hardening [σsh(ε)] pose a significant challenge. Extensive elastic-plastic finite ...

A weighted-average method for determining uniaxial, true tensile stress vs. strain relation after necking is presented for strip shaped samples. The method requires identification of a lower and an upper bound for the true stress-strain function after necking and expresses the true stress-strain relation as the weighted average of these two bounds. The weight factor is determined iteratively by...

In a recent paper, De Baets et al. have characterized the fuzzytolerance and fuzzy equivalence relations that a given strict order relation iscompatible with. In this paper, we generalize this characterization by consideringan arbitrary (crisp) relation instead of a strict order relation, while payingattention to the particular cases of a reflexive or irreflexive relation. The reasoninglargely ...

BACKGROUND Previous studies have shown that psychosocial working conditions characterized by high psychological demands and low decision latitude (i.e., high strain work) are associated with increased risk of depressive symptoms. Little is known, however, concerning how this association may be modified by factors outside the working environment. This article examines the modifying role of priva...

Nowadays, the technology intends to use materials such as magnesium alloys due to their high strength to weight ratio in engine components. As usual, engine cylinder heads and blocks has made of various types of cast irons and aluminum alloys. However, magnesium alloys has physical and mechanical properties near to aluminum alloys and reduce the weight up to 40 percents. In this article, a new ...

ABSTRACT- Mechanical damage degrades fruit quality in the chain from production to the consumption. Damage is due to static, impact and vibration loads during processes such as harvesting, transportation, sorting and bulk storage. In the present study finite element (FE) models were used to simulate the process of static bruising for apple fruits by contact of the fruit with a hard surface. Thr...

In this paper the effect of different hardening models in simulating the U-bending process for AA5754-O and DP-Steel, taking a benchmark of NUMISHEET 93 2-D draw bending, has been discussed. The hardening models considered in simulations are: isotropic hardening, pure (linear) kinematic hardening and combined (nonlinear kinematic) hardening. The influence of hardening models on predicting sprin...

Due to the large reversible strains achievable through the stress-induced austenite-martensite phase transformation in NiTi alloys, NiTi has replaced stainless steel in the majority of large-strain biomedical applications such as root canal enlargement. However, the pseudoelasticity of NiTi is currently overshadowed by the short fatigue life of NiTi wires used in this low cycle (200-2000 rpm), ...