تحلیل ترک نیم بیضوی در مخازن کروی تحت فشار از جنس مواد مدرج تابعی

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده فنی و مهندسی، دانشگاه قم، قم، ایران

چکیده

از مهمترین تحلیل‌ها در طراحی سازه‌های مختلف مخصوصا مخازن تحت فشار و بررسی ایمنی آن‌ها، تحلیل مکانیک شکست می‌باشد. یکی از پارامترهای مهم در علم مکانیک شکست، بررسی ضریب شدت تنش ترک‌های موجود در دیواره مخزن است. در مطالعه حاضر، رفتار یک ترک نیم بیضوی در مخزن تحت فشار کروی ساخته شده از جنس مواد مدرج تابعی با استفاده از نرم افزار اجزاء محدود آباکوس مورد مطالعه قرار گرفته است. اثر پارامترهایی از قبیل هندسه ترک، دو ترک داخلی و خارجی همزمان، توزیع فشار، توزیع بار‌‌حرارتی، تغییر‌ات خواص ماده مدرج تابعی و شرایط تکیه‌گاهی بر مقدار ضریب شدت تنش بررسی شده است. برای مدل‌سازی و تحلیل ضریب شدت تنش در این نوع مخزن از توابع مختلف توانی، نمایی و خطی در قالب کد متلب و همینطور یک کد سابروتین استفاده شده است. هندسه ترک نیز از عوامل مهمی است که بر ضریب شدت تنش اثر بسزایی می‌گذارد. بطوریکه با افزایش مقدار a/c ضریب شدت تنش نیز افزایش می‌یابد. همچنین بررسی شرایط تکیه‌گاهی نشان می‌دهد که با افزایش تعداد پایه‌ها، ضریب شدت تنش نیز افزایش می‌یابد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Analysis of the semi-elliptical crack in the FGM spherical pressure vessels

نویسندگان [English]

  • Mohammad Salari
  • Fatemeh Ebrahimi
Department of mechanical engineering, university of Qom
چکیده [English]

One of the most important analyses in the design of various structures, especially pressure vessels and their safety is the fracture mechanics. One of the important parameters in fracture mechanics is the study of the stress intensity factor of cracks in the tank wall. In the present study, the behavior of a semi-elliptical crack in a spherical pressure vessel made of functionally graded materials has been studied using Abaqus finite element software. The effects of parameters such as crack geometry, simultaneous internal and external cracks, pressure distribution, thermal load distribution, changes in the properties of the functionally graded material, and support conditions on the value of the stress intensity factor have been investigated. To model and analyze the stress intensity factor in this type of tank, various power, exponential, and linear functions have been used in the form of MATLAB code as well as a subroutine code. Crack geometry is also an important factor that has a significant effect on the stress intensity factor. So with an increase in the a/c value, the stress intensity factor also increases. Also, the examination of the support conditions shows that with the increase in the number of foundations, the stress intensity factor also increases.

کلیدواژه‌ها [English]

  • FGM
  • Stress intensity factor
  • Semi-elliptical crack
  • Spherical pressure vessels
  • Thermal analysis
[1] N. Noda, Z. H. JIN, Thermal Stress intensity factors for a crack in a strip of a functionally gradient material, Journal Solids Structure, 30(8) (1993) 1039-1056.
[2] Y.Z. Chen, Stress intensity factors in a finite cracked cylinder made of functionally graded materials, Pressure Vessels and Piping, 81(12) (2004) 941-947.
[3] A.M. Afsar, M. Anisuzzama, Stress intensity factors of two diametrically opposed edge cracks in a thick-walled functionally graded material cylinder, Engineering Fracture Mechanics, 74(10) (2007) 1617-1636.
[4] M. R. Nami, H. Eskandari, Three-dimensional investigations of stress intensity factors in a thermo-mechanically loaded cracked FGM hollow cylinder, Pressure Vessels and Piping, 89 (2012) 222-229.
[5] A. Shaghaghi Moghaddam, M. Alfano, R. Ghajar, Determining the mixed mode stress intensity factors of surface cracks in functionally graded hollow cylinders, Materials and Design, 43 (2013) 475-484.
[6] I. Eshraghi, N. Soltani, M. Rajabi, Transient stress intensity factors of functionally graded hollow cylinders with internal circumferential cracks, Solids and Structures, 13(9) (2016) 1738-1762.
[7] ] H. Mahbadi, Stress Intensity Factor of Radial Cracks in Isotropic Functionally Graded Solid Cylinders, Engineering Fracture Mechanics, 180 (2017) 115-131.
[8] H. Eskandari, Three-Dimensional Finite Element Analysis of Stress Intensity Factors in a Spherical Pressure Vessel with Functionally Graded Coating, Solid Mechanics, 9(4) (2017) 751-759.
[9] M. R. Ghafoor Elahi, M. Mahdizadeh Rohi, Calculation Of Stress intensity factor for an internal circumferential crack in a rotating functionally graded thick-walled hollow circular cylinder under thermal shock, Archive of Mechanical Engineering, 4 (2017) 455-479.
[10] N. Habibi, S. Asadi, R. Moradikhah, Evaluation of SIF in FGM Thick-walled Cylindrical Vessel, Stress Analysis, 2(1) (2017) 57-68.
[11] M. Noroozi, A. Ghassemi, A. Atrian, M. Vahabi, Multiple Cylindrical Interface Cracks in FGM Coated Cylinders under Torsional Transient Loading, Theoretical and Applied Fracture Mechanics, 97 (2018) 258-264.
[12] A. Shaghaghi Moghaddam, M. Alfano, Thermoelastic analysis of surface cracks in FGMs hollow cylinders using the interaction energy integral method, Engineering Fracture Mechanics, 202 (2018) 103-115.
[13] S. M. Nabavi, A. Zareei, Determination of steady state thermal stress intensity factors for semi-elliptical circumferential cracks in cylinders, Amirkabir J. Mech. Eng., 49(4) (2018) 665-672.
[14] N. Habibi, H. Bahrampour, Estimation of the SIF in FGM spherical pressure vessel, Australian Journal of Mechanical Engineering, 20(4) (2022) 911-926.
[15] MatWeb: Online Materials Information Resource. https://matweb.com
[16] Mahmoudi Monfared, Mojtaba; Yagoubi, Reza; "Evaluation of the stress intensity coefficient for an edge crack located in a beam made of functionally graded materials under a failure mechanics mode loading" 25th Annual International Conference of Mechanical Engineering of Iran, 2(2016) 2-14 (in Persian)