Constant-flux gravity currents of viscoplastic fluid remain axisymmetric when extruded onto a dry horizontal plane. However, if the plane is coated with shallow layer water, current suffers dramatic non-axisymmetric instability in which localized $v$ -shaped cuts appear outer edge where contact water. These ‘fractures’ lengthen and guide subsequent radial outflow, leading to distinctive flower-...

Slab method of analysis has been used for solving metal forming problems for a long time. However it has been restricted to plane strain and axisymmetric problems due to limitations in its formulations. In this paper a new formulation has been proposed so that it could be applied to three dimensional problems in metal forming. A parametric slab has been considered in this analysis and the force...

The yield criterion of many metallic materials differs from the von Mises criterion. However, available upper bound solutions are almost all restricted to this objective present paper was derive an solution based on a generalized for evaluating extrusion and drawing force, assuming conical die. method conventional used in conjunction with development is necessary, since work function not readil...

The viscoelastic character of polymer solutions and melts gives rise to instabilities that are not seen in the flows of Newtonian liquids. In industrial applications such as coating and extrusion, these so-called “elastic” instabilities can impose a limitation on the throughput. Hence, it is important to understand, and if possible, to suppress them. The first instability we study is the phenom...

hot-melt extrusion is one of the most widely applied processing technologies in the plastic, rubber and food industry. today this technology has found its place in the array of pharmaceutical manufacturing operations. melt extrusion process are currently applied in the pharmaceutical field for the manufacture of a variety of dosage forms and formulations such as granules, pellets, tablets, supp...

The hydrostatic extrusion is a new method of extrusion process. The most important advantage of this method is reduction of friction and close tolerance for the coating thickness. In this study, the hydrostatic extrusion simulation of bimetallic wires has performed using of finite element method. In the following the advantages of hydrostatic extrusion compared to the direct extrusion are prese...

Abstract Introduction In bioprinting techniques, tissue engineering from 3D models to generate the desired geometry is as important cell proliferation, it will be key survival of printed and its functional success. Methods Alginate-based hydrogels were used because they are most widely by scientific community for bioprinting. The alginate-based characterised using a rheometer obtain boundary co...