@article { author = {Nikpour, R. and Mahbadi, H.}, title = {Stress intensity factor for a small radial crack located on external edge of a rotating viscoelastic cylinder subjected to internal pressure and temperature distribution}, journal = {Sharif Journal of Mechanical Engineering}, volume = {37.3}, number = {1}, pages = {17-26}, year = {2021}, publisher = {Sharif University of Technology}, issn = {2676-4725}, eissn = {2676-4733}, doi = {10.24200/j40.2020.54689.1539}, abstract = {In this research, stress intensity factor of a small radial crack in a rotating thick cylinder made of viscoelastic materials subjected to internal pressure and radial temperature distribution is investigated. The radial crack is assumed to be located at the outer edge of the cylinder. The Zener model (i.e., standard three parameter solid) is applied to simulate the viscoelastic behavior of the cylinder. To obtain the stress intensity factor of the viscoelastic cylinder, the problem of uncracked viscoelastic cylinder subjected to internal pressure and radial temperature distribution is analyzed with plane strain assumptions. Then, the hoop stress distribution is determined. Finally, by assuming the small crack length and applying the superposition method, the problem of cracked viscoelastic cylinder is replaced by the problem of cracked viscoelastic cylinder subjected to determined average stress in the previous step. By employing the proper geometry factor, the stress intensity factor of the viscoelastic cylinder is determined. A parameter study is performed to investigate the effects of various parameters on the stress intensity factor of the cylinder. To validate the results, the problem of viscoelastic cracked cylinder is simplified to an elastic cracked cylinder by neglecting the viscoelastic terms, and the data obtained in the present work are compared with those given in the literature search. The results show that the proposed method is quite capable of estimating the stress intensity factor of small cracks in structures made of viscoelastic materials. A parameter study is performed to investigate effect of various parameters on stress intensity factor of the cylinder. The parameter study shows that a) the stress intensity factor of the viscoelastic cylinder in early moments of loading is higher than its equivalent elastic cylinder, b) increasing the elastic properties of the viscoelastic material results in higher stress intensity factor, and increasing the viscous properties of the material decreases the stress intensity factor.}, keywords = {Stress intensity factor,viscoelastic cylinder,Zener model,Internal pressure,Thermal distribution}, title_fa = {ضریب شدت تنش ترک کوچک شعاعی واقع بر لبه ی خارجی استوانه ی چرخان ویسکوالاستیک تحت فشار داخلی و توزیع حرارتی}, abstract_fa = {در این مقاله ضریب شدت تنش ترک کوچک شعاعی در لبه‌ی خارجی یک استوانه‌ی جدار ضخیم ویسکوالاستیک دوار تحت فشار داخلی و توزیع حرارتی مورد بررسی قرار گرفته است. به‌منظور مدل‌سازی رفتار ویسکوالاستیک استوانه، از مدل جامد سه پارامتری زنر بهره گرفته شده است. ابتدا توزیع تنش در استوانه‌ی ویسکوالاستیک بدون ترک تعیین شده است. سپس با استفاده از روش برهم‌نهی و انتخاب ضریب هندسی مناسب، مسئله‌ی استوانه‌ی ترک‌دار بررسی شده است. نهایتاً، اثر پارامترهای مختلف بر روی ضریب شدت تنش بررسی شده است. با حذف اثر ویسکوالاستیک در استوانه، ضرایب شدت تنش به دست آمده در مقاله‌ی حاضر با نتایج موجود در سوابق علمی مسئله مقایسه شده است. نتایج به دست آمده نشان می‌دهد که با افزایش خواص الاستیک ماده ضریب شدت تنش افزایش و با افزایش خواص ویسکوز ماده ضریب شدت تنش کاهش می‌یابد.}, keywords_fa = {ضریب شدت تنش,استوانه‌ی ویسکوالاستیک,مدل زنر,فشار داخلی,توزیع‌حرارتی}, url = {https://sjme.journals.sharif.edu/article_22150.html}, eprint = {https://sjme.journals.sharif.edu/article_22150_84e438a27cb1d5f7dec2526145f6ad5d.pdf} }