This paper presents an automated tool for local, conformal refinement of all-hexahedral meshes based on the insertion of multidirectional twist planes into the spatial twist continuum. The refinement process is divided into independent refinement steps. In each step, an inserted twist plane modifies a single sheet or two parallel hex sheets. Six basic templates, chosen and oriented based on the...

The effect of geometrical parameters involved in vortex extrusion (VE) die design, on AA1050 aluminium alloy processed by VE were investigated using finite element analysis (FEA) and response surface methodology (RSM). For this, VE die length (L), reduction in area (RA), twist angle , and position of control points in Beziers' formulation (C1) were considered as input parameters and strain inho...

In the present work, effects of loading scheme and strain reversal on structure evolution are studied by using high pressure torsion (HPT) and twist extrusion (TE) techniques. High purity aluminum (99.99%) was processed at room temperature up to a total average equivalent strain of ~4.8 by TE and HPT with two deformation modes: monotonic and reversal deformation with a step of 12 ̊ rotation. It ...

Introduction Left ventricular (LV) twist is believed to store potential energy and plays an important role in generating diastolic suction. Recent advances in echocardiography techniques have allowed quantification of LV twist. The aim of the present study was to compare LV twist and torsion in healthy human subjects determined by velocity vector imaging (VVI) and tissue Doppler imaging (TDI) a...