Large deformations of thin-walled circular tubes under transverse loading—II

Pinched Material Einstein Space-Time Produces Accelerated Cosmic Expansion

“…That way cosmological data and observation collected over a very long period culminating in several deserving Nobel Prizes in Physics has fused various theories together and confirmed the reality of Hawking's radiation, Unruh's temperature, antigravity and Rindler space-time all apart of completing the magnificent work of Einstein's relativity, PlanckBohr-Heisenberg's quantum mechanics and Boltzmann thermodynamics [24] as indicated in the eminent work of T. Padmanabhan and his school [32] [33]. One could of course argue that the present derivation based on an analogy between metal forming, pinching of elastic types and the real behavior of a material space-time micropolar elasticity [76] [78] is less fundamental than previous derivations starting from the zero set as a prequantum particle and the empty set as a pre-quantum wave [36]- [38] [77]. However, this is a largely subjective judgement and a matter of taste and personal philosophical stance [24].…”

Finite element simulation of the squaring circular tube

“…The relationship of equivalent stressσ and equivalent plastic strainε p of the material is represented by an n-power law of the form σ = Kε n p (3) in order to model the hardening behavior in which n denotes the strain hardening exponent and K is a material constant.…”

“…In particular, seamless tubing, which is usually made by piercing and extrusion, is used in high-temperature or high-pressure applications as well as for transporting gas or chemical liquids. The use of circular tubes in energy absorbing systems is an attractive topic and has been discussed by several authors [1][2][3][4][5]. The circular tube compressed between two rigid, parallel plates has also been discussed [6][7][8][9][10] to explore the characteristics of collapse occurrence.…”

The shaping of a circular tube into a symmetric square-tube by finite-element modeling

“…In particular, seamless tubing, usually made by piercing and extrusion, is readily used in high temperature or pressure applications such as nature gas and chemical liquid transportation, and construction of boilers and heat exchangers. The utilization of circular tubes in energy absorbing systems is a significant and interesting topic that has been studied by several authors [1][2][3][4][5]. Moreover, the compression of circular tube between two rigid and parallel plates was discussed by [6][7][8][9][10] in order to explore the characteristics of collapse mode.…”