Abstract    In this study a non-associated viscoplastic flow rule (NAVFR) with combining von Mises and Tresca loci in place of yield and plastic potential functions and vice verse is presented. With the aid of fully implicit time stepping scheme and discussing the other studies on plastic potential flow rules and also experimental results it is shown that the proposed NAVFR can be adopted to forecast the experimental events more accurate than the conventional associated viscoplastic flow rules (AVFR).

Keywords    Rate-Dependant Non-associated Viscoplastic Flow Rule, Fully Implicit Time Stepping Scheme, Internally Pressurized Thick Walled Cylinder.

چکیده    در این پژوهش قانون جریان ویسکوپلاستیسیته ناوابسته با ترکیب سطوح تسلیم ون مایزز و ترسکا به جای توابع تسلیم و پتانسیل پلاستیک و برعکس ارائه شده است. به کمک روش مرحله ای زمانی کاملا غیرصریح و همچنین بحث در مورد مطالعات انجام شده روی توابع پتانسیل پلاستیک ارائه شده توسط سایر مولفین و همچنین نتایج آزمایشگاهی نشان داده خواهد شد که قانون جریان ویسکوپلاستیسیته ناوابسته ارائه شده از قانون جریان وابسته مرسوم نظیر خود نتایج آزمایشگاهی را دقیق تر پیش بینی می نماید.

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