تحلیل شکست دینامیکی مود ترکیبی ورق مدرج تابعی با روش بدون مش

علوم کاربردی و محاسباتی در مکانیک

مقاله 1، دوره 25، شماره 2، شهریور 1393، صفحه 1-18   

نوع مقاله: مقاله پژوهشی

شناسه دیجیتال (DOI): 10.22067/fum-mech.v25i2.23059

نویسندگان

علی عبداللهی فر^{* 1}؛ محمد رحیم نامی¹؛ بهادر سرانجام²

¹دانشگاه شیراز

²پژوهشکده هوا دریا

چکیده

در این مقاله تحلیل ترک مود ترکیبی ورق مدرج تابعی با استفاده از روش MLPG انجام شده است و تأثیر تغییرات مقدار و زاویه‌ی گرادیان خواص بر ضرایب شدت تنش دینامیکی مود اول، دوم و مؤثر دینامیکی بررسی شده است. برای حل معادلات وابسته به زمان که توسط MLPG شکسته شده اند روش های تفاضل مرکزی و نیومارک استفاده شده است. اگر چه روش انتگرال J یکی از روش های مرسوم در محاسبه‌ی ضریب شدت تنش است اما به‌طور کلی این روش برای مواد مدرج تابعی قابل استفاده نیست. بنابراین در این مقاله برای محاسبه‌ی ضریب شدت تنش از انتگرال مستقل از مسیر J* که برای مواد ناهمگن فرمول بندی شده، استفاده گردیده است. نتایج نشان می-دهد که روش حاضر تطابق خوبی با حل دقیق و سایر حل های موجود دارد. هم‌چنین نتایج نشان می دهد، که حداکثر و حداقل مقدار ضریب شدت تنش مؤثر برای E2/E1>1 به‌ترتیب در زاویه‌ی گرادیان خواص 0 و 90 درجه رخ می دهد و برای E2/E1

کلیدواژه‌ها

تحلیل شکست دینامیکی مود ترکیبی؛ روش بدون مش محلی پتروف-گالرکین؛ زاویه گردایان خواص؛ مواد مدرج تابعی؛ روش نیومارک؛ روش تفاضل مرکزی

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