فهرست:
فصل 1: مقدمه 1
1-1 مقدمه 2
1-2 مکانیک آسیب پیوسته 4
1-3 هدف از انجام پژوهش 5
1-4 چکیده مباحث مطرح شده در این پایاننامه 5
فصل 2: مروری بر تحقیقات انجام شده 7
2-1 مکانیک آسیب پیوسته 8
2-2 اندرکنش خزش– خستگی 13
فصل 3: معادلات حاکمه 19
3-1 مقدمه 20
3-2 ماهیت و متغیرهای آسیب 20
3-3 انواع آسیب 23
3-4 مفاهیم پایه 27
3-4-1 پارامتر آسیب 27
3-4-2 مفهوم تنش مؤثر 28
3-4-3 اصل کرنش معادل 30
3-4-4 ارتباط کرنش و آسیب 30
3-4-5 آستانه آسیب 33
3-5 فرمول بندی ترمودینامیکی آسیب 35
3-5-1 ترمودینامیک آسیب 35
3-5-2 چارچوب کلی 36
3-5-3 پتانسیل حالت برای آسیب همسان 40
3-5-4 قوانین سینتیک رشد آسیب 41
3-6 معادلات الاستو-(ویسکو-)پلاستیسیته کوپل با آسیب 45
3-6-1 معادلات اساسی (ویسکو-)پلاستیسیته بدون کوپل با آسیب 45
3-6-2 معادلات کوپل بین پلاستیسیته و آسیب 47
3-7 مدلسازی اندرکنش خزش-خستگی 49
3-8 اندازهگیری آسیب 50
3-8-1 روش تغییرات مدول الاستیسیته 53
فصل 4: مدلسازی روتور 55
4-1 مقدمه 56
4-2 شرایط کارکرد و هندسه روتور 57
4-2-1 شرایط کارکرد 57
4-2-2 هندسه روتور 60
4-3 شرایط مرزی و بارهای اعمالی 64
4-4 شرایط دمایی 65
4-5 انتخاب المان و شبکهبندی مدل 68
4-6 گامهای حل 72
فصل 5: تعیین خواص مکانیکی جنس روتور 74
5-1 مقدمه 75
5-2 شناسایی جنس روتور توربین گاز 75
5-3 آزمون کشش ساده و دورهای 78
5-3-1 نتایج آزمون کشش 80
5-3-2 تعیین پارامترهای مدل سختی سینماتیکی 83
5-3-3 تعیین پارامترهای مدل آسیب 87
5-3-4 تعیین مقدار بحرانی پارامتر آسیب 91
5-4 آزمون رهایش 97
5-4-1 تعیین پارامترهای مدل ویسکوز نورتن 100
5-5 نتیجهگیری 104
فصل 6: نتایج و بررسی 105
6-1 مقدمه 106
6-2 نتایج مربوط به شبیهسازی المان محدود 106
6-2-1 وضعیت فعلی روتور 107
6-2-2 تخمین عمر باقیمانده روتور 114
6-2-3 بررسی نتایج 117
6-3 تخمین عمر به کمک آزمون رپلیکا 128
6-3-1 روش رپلیکا 128
6-3-2 انجام آزمون رپلیکا بر روی روتور توربین 129
6-3-3 مشاهده نمونههای آزمون رپلیکا توسط SEM 131
فصل 7: نتیجهگیری و پیشنهادات 135
7-1 نتیجه گیری 136
7-2 پیشنهادات 137
فهرست منابع 139
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