مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

بررسی سه بعدی رفتارهای مکانیکی غیرخطی وابسته به دمای ورق‌های مستطیلی مدرج تابعی روی پایه الاستیک وینکلر-پسترناک

نویسندگان
1 دانشجوی کارشناسی، مهندسی‌ مکانیک، دانشگاه گیلان
2 دانشیار دانشگاه گیلان
چکیده
در این مقاله به بررسی رفتار مکانیکی غیرخطی ورقهای مستطیلی مدرج تابعی در جهت ضخامت وابسته به دما با استفاده از تئوری الاستیسیته سه بعدی روی پایه های الاستیک وینکلر-پسترناک پرداخته شده است. فرض میشود خواص مواد سازنده وابسته به دما می باشند و براساس یک قانون توانی در راستای ضخامت تغییر می کنند. با در نظر گرفتن رابطه کرنش غیرخطی گرین-لاگرانژ، اثرات غیرخطی هندسی در محاسبات منظور شده است. پس از بدست آوردن انرژی‌های کرنشی و جنبشی و کار ناشی از نیروی خارجی و در نظر گرفتن اثرات دما و بستر الاستیک، از اصل همیلتون برای بدست آوردن معادلات حاکم سه بعدی استفاده می شود. برای حل مسائل مربوط به رفتار مکانیکی سیستم، ابتدا از روش تربیع دیفرانسیلی تعمیم یافته برای گسسته سازی معادلات کوپل غیرخطی در فضای مکان استفاده میشود. سپس، با استفاده از روش گلرکین عددی برای حل مساله ارتعاشات آزاد، معادلات تبدیل به معادلات دیفرانسیل معمولی تابع زمان می شوند و با استفاده از روش گسسته سازی متناوب زمانی در حوزه زمان گسسته می‌شود. در نهایت، از الگوریتم طول کمان برای یافتن پاسخ فرکانسی سیستم بهره گرفته می‌شود. برای حل مساله خمش غیرخطی، با صرف نظر کردن از اثر اینرسی و استفاده از الگوریتم طول کمان، ماکزیمم خمش بر حسب نیرو به دست می آید. اثرات پارامترهای مانند نسبت طول به ضخامت، ثابت های وینکلر و پسترناک، تغییر دمای یکنواخت و خطی و شاخص کسر حجمی بر پاسخ فرکانسی و ماکزیمم خمش ورقهای مدرج تابعی با شرایط مرزی مختلف به تفضیل مورد بررسی قرار گرفته است.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Three dimensional analysis of temperature-dependent nonlinear mechanical behaviors of functionally graded rectangular plates resting on Winkler–Pasternak elastic foundation

نویسندگان English

Y. Gholami 1
Reza Ansari 2
1 Department of Mechanical Engineering, University of Guilan, Rasht, Iran
چکیده English

The temperature-dependent nonlinear mechanical behaviors of functionally graded rectangular plates in the thickness direction resting on Winkler–Pasternak elastic foundation are investigated using the three-dimensional theory of elasticity. The material properties are temperature-dependent and varied in the thickness direction based on a power-law. Considering the nonlinear Green-Lagrange strain relation, the geometric nonlinearity is taken into account. After obtaining the potential strain, kinetic energies, taking into account the effects of the temperature and the elastic foundation, the Hamilton’s principle is used to derive the nonlinear three-dimensional governing equations and corresponding boundary conditions. To solve the nonlinear free vibration problem, first, the generalized differential quadrature (GDQ) method is used to discretize the nonlinear coupled governing equations in the space domain. Then, the obtained equations are converted to the time-dependent ordinary differential equations using the numerical-based Galerkin scheme and the time periodic discretization (TPD) are used to discretize them in the time domain. Finally, the arc-length method is employed to find the frequency-response of system. Also, to solve the nonlinear bending problem, by neglecting the effect of inertia and using the arc length algorithm, the maximum deflection versus the applied load is obtained. The effects of different parameters such as length-to-thickness ratio, Winkler–Pasternak elastic foundation coefficients, uniform and linear temperature rises and volume fraction index on the frequency response and maximum deflection of functionally graded plates with various edge conditions are studied.

کلیدواژه‌ها English

Functionally graded plate
Nonlinear mechanical behaviors
3D theory of elasticity
Numerical solution procedure
[1] M. Koizumi, FGM activities in Japan, Composites Part B: Engineering, Vol. 28, No. 1, pp. 1-4, 1997.
[2] J. Reddy, Analysis of functionally graded plates, International Journal for Numerical Methods in Engineering, Vol. 47, No. 1-3, pp. 663-684, 2000.
[3] J. Yang, H.-S. Shen, Dynamic response of initially stressed functionally graded rectangular thin plates, Composite Structures, Vol. 54, No. 4, pp. 497-508, 2001.
[4] Z.-Q. Cheng, S. Kitipornchai, Membrane analogy of buckling and vibration of inhomogeneous plates, Journal of engineering mechanics, Vol. 125, No. 11, pp. 1293-1297, 1999.
[5] R. Batra, J. Jin, Natural frequencies of a functionally graded anisotropic rectangular plate, Journal of Sound and Vibration, Vol. 282, No. 1, pp. 509-516, 2005.
[6] L. Qian, R. Batra, L. Chen, Static and dynamic deformations of thick functionally graded elastic plates by using higher-order shear and normal deformable plate theory and meshless local Petrov–Galerkin method, Composites Part B: Engineering, Vol. 35, No. 6, pp. 685-697, 2004.
[7] H. Matsunaga, Free vibration and stability of functionally graded plates according to a 2-D higher-order deformation theory, Composite structures, Vol. 82, No. 4, pp. 499-512, 2008.
[8] M. Alizadeh, A. Alibeigloo, Static and free vibration analyses of functionally graded sandwich plates using three dimensional theory of elasticity, Modares Mechanical Engineering, Vol. 14, No. 10, 2015.
[9] H. Zafarmand, M. Kadkhodayan, Three-dimensional static analysis of thick functionally graded plates using graded finite element method, Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, Vol. 228, No. 8, pp. 1275-1285, 2014.
[10] E. A. Shahrbabaki, A. Alibeigloo, Three-dimensional free vibration analysis of rectangular nanoplates based
on nonlocal theory of elasticity, Modares Mechanical Engineering, Vol. 15, No. 11, pp. 54-62, 2015.
[11] Sh. Hosseini- Hashemi, H. Akhavan, M. Fadaee, Exact Closed-form Free Vibration Analysis of Moderately Thick Rectangular Functionally Graded Plates with Two Bonded Piezoelectric Layers, Modares Mechanical Engineering, Vol. 11, No. 3, pp. 57-74, 2011.
[12] R. Nazemnezhad, S. Hosseini-Hashemi, M. Kermajani, S. Amirabdollahian, Exact solutions for free vibration of lévy-type rectangular nanoplates via nonlocal third-order plate theory.
[13] A. Bakhsheshy, K. Khorshidi, Free vibration of functionally graded rectangular nanoplates in thermal environment based on the modified couple stress theory, Modares Mechanical Engineering, Vol. 14, No. 15, pp. 323-330, 2015.
[14] S. P. Timoshenko, S. Woinowsky-Krieger, Theory of plates and shells: McGraw-hill, 1959.
[15] S. S. Vel, R. Batra, Three-dimensional exact solution for the vibration of functionally graded rectangular plates, Journal of Sound and Vibration, Vol. 272, No. 3, pp. 703-730, 2004.
[16] Z. Zhong, E. Shang, Three-dimensional exact analysis of a simply supported functionally gradient piezoelectric plate, International Journal of Solids and Structures, Vol. 40, No. 20, pp. 5335-5352, 2003.
[17] Z. Zhong, T. Yu, Vibration of a simply supported functionally graded piezoelectric rectangular plate, Smart materials and structures, Vol. 15, No. 5, pp. 1404, 2006.
[18] R. K. Bhangale, N. Ganesan, Free vibration of simply supported functionally graded and layered magneto-electro-elastic plates by finite element method, Journal of Sound and Vibration, Vol. 294, No. 4, pp. 1016-1038, 2006.
[19] A. Goldsmith, Handbook of Thermophysical Properties of Solid Materials: Elements: Macmillan, 1961.
[20] J. Yang, H.-S. Shen, Vibration characteristics and transient response of shear-deformable functionally graded plates in thermal environments, Journal of Sound and Vibration, Vol. 255, No. 3, pp. 579-602, 2002.
[21] Q. Li, V. Iu, K. Kou, Three-dimensional vibration analysis of functionally graded material plates in thermal environment, Journal of Sound and Vibration, Vol. 324, No. 3, pp. 733-750, 2009.
[22] C. Shu, Differential quadrature and its application in engineering, London: Springer Science & Business Media, 2012.
[23] R. Ansari, M. F. Shojaei, V. Mohammadi, R. Gholami, M. Darabi, Nonlinear vibrations of functionally graded Mindlin microplates based on the modified couple stress theory, Composite Structures, Vol. 114, pp. 124-134, 2014.
[24] S. Ibrahim, B. Patel, Y. Nath, Modified shooting approach to the non-linear periodic forced response of isotropic/composite curved beams, International journal of non-linear mechanics, Vol. 44, No. 10, pp. 1073-1084, 2009.
[25] R. Ansari, A. Shahabodini, M. F. Shojaei, Nonlocal three-dimensional theory of elasticity with application to free vibration of functionally graded nanoplates on elastic foundations, Physica E: Low-dimensional Systems and Nanostructures, Vol. 76, pp. 70-81, 2016.
[26] R. Aghababaei, J. Reddy, Nonlocal third-order shear deformation plate theory with application to bending and vibration of plates, Journal of Sound and Vibration, Vol. 326, No. 1, pp. 277-289, 2009.
[27] H.-T. Thai, D.-H. Choi, A simple first-order shear deformation theory for the bending and free vibration analysis of functionally graded plates, Composite Structures, Vol. 101, pp. 332-340, 2013.