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تسجيل مستخدم جديدحل رقمي لضغط الصدمة والصعود لخصائص المواد العامة
Numerical solution of shock and ramp compression for general material properties
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تأليف
Damian C. Swift
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صُمِمَتْ صيغة عامة لتمثيل الأنماط المادية للتطبيقات في التحميل الديناميكي. تم تصميم أساليب رقمية لحساب الاستجابة للصدمة والضغط المدرج والإفراز المدرج، تشمل الحلول السابقة لمعادلات الدولة المكعبة. وقد وجد أن الأساليب الرقمية كانت مرنة وثابتة، وتطابقت النتائج التحليلية بدقة عالية. تم ربط الحلول الأساسية للضغط المدرج والصدمة لحل المسارات الإجهاد المركب، مثل الأثر الصدمي المسبب والتفاعل الصدمي مع واجهة مستوية بين مواد مختلفة. هذه الحسابات تصحح الكثير من الفيزياء التي تشهدها التجارب الديناميكية المادية دون الحاجة إلى تحليلات محددة الموقع. تم إجراء حسابات بالأمثلة لتاريخ التحميل في المعادن، والتي توضح تأثير العمل البلاستيكي على الحرارات الناتجة في التجارب القريبة من الإحتسابية والإفراز الصدمي، وتأثير الانتقال المرحلي.
A general formulation was developed to represent material models for applications in dynamic loading. Numerical methods were devised to calculate response to shock and ramp compression, and ramp decompression, generalizing previous solutions for scalar equations of state. The numerical methods were found to be flexible and robust, and matched analytic results to a high accuracy. The basic ramp and shock solution methods were coupled to solve for composite deformation paths, such as shock-induced impacts, and shock interactions with a planar interface between different materials. These calculations capture much of the physics of typical material dynamics experiments, without requiring spatially-resolving simulations. Example calculations were made of loading histories in metals, illustrating the effects of plastic work on the temperatures induced in quasi-isentropic and shock-release experiments, and the effect of a phase transition.
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