Optimization of Axisymmetric Extrusion Die Profiles
الموضوعات : فصلنامه شبیه سازی و تحلیل تکنولوژی های نوین در مهندسی مکانیک
حسن نحوی
1
(دانشیار، دانشکده مکانیک ، دانشگاه آزاد اسلامی واحد خمینی شهر.)
مهدی حسن زاده
2
(مربی، گروه مکانیک ، دانشگاه آزاد اسلامی واحد کردکوی)
الکلمات المفتاحية: Optimization, Finite Element Method, Extrusion, Bezier curves, Constant strain rate,
ملخص المقالة :
In this research, optimization process of axisymmetric extrusion dies is proposed. Plastic zone is analyzed using finite element method in the Eulerian system with flow formulation. The die profiles are defined by Bezier curves with six control points. Two effective functions are considered in this research; standard deviation of the strain rate and the rate of energy consumption during extrusion process. A coupled numerical approach of finite element analysis in Eulerian system and the non-gradient Nelder-Mead method is utilized to determine optimum die profiles. Results show that optimized die has higher uniformity in strain rate distribution and less strain values with respect to the non-optimum conical die. In the case of minimizing energy consumption rate, results show that for the die with constant and variable lengths and low friction, the die profile tends to the stream line. In die with variable length and high friction, friction has more effective role in optimization and the die length tends towards lower lengths during optimization.
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