DOMAIN-BOUNDARY ELEMENT METHOD FOR ELASTODYNAMICS OF FUNCTIONALLY GRADED THICK-WALLED CYLINDERS AND ANNULLAR COATINGS

Download

Abdelrahim Abeidi - PhD thesis.pdf

Date

2022-12-16

Author

Abeidi, Abdelrahim

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

118
views

77
downloads

In this thesis, a new computational technique using domain boundary element method (D-BEM) will be developed to perform the elastodynamic analysis of functionally graded thick-walled cylinders and annular coatings. The thick-walled cylinder material properties are varying along the radial direction according to a power distribution law of volume fraction; hence, the cylinder can withstand pressure shock types of loadings. These mechanical loads are described by uniform dynamic pressures at the inner and outer edges. Therefore, the FGM thick-walled cylinder is subjected to axisymmetric external loading in plane strain condition. The domain boundary element method will be implemented to solve the integral equations achieved by using the static fundamental solution to write the governing differential equation in the residual form. However, since the problem is dynamic, time dependent, isoparametric quadrilateral elements will be proposed to discretize the domain. The integral equations will be computed for each element and a system of time dependent ordinary differential equations will result. The time response is obtained by using Houbolt method of time marching scheme to solve the system of ordinary differential equations. Therefore, the proposed D-BEM method is verified by considering various researches, which study the elastodynamics of FGM thick-walled cylinders subjected to different mechanical loadings on the inner surface, such as: mechanical shock and exponential loadings. Furthermore, the FGM thick-walled cylinder elastodynamic response has been studied using the D-BEM in plane stress and plane strain conditions. An internal and external ramp dynamic pressure and an internal exponential dynamic pressure are considered in the study of the composite thick-walled cylinders and annular coatings. The radial displacement response, radial and hoop stresses are calculated at different material property gradation values. Moreover, for the pressure shock loadings selected, the spatial radial displacement, spatial radial and hoop stresses are studied.

Subject Keywords

Thick-Walled Cylinder, Annular Coatings, FGM, Elastodynamic, D-BEM

URI

https://hdl.handle.net/11511/101781

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Domain-boundary element method for elastodynamics of functionally graded Timoshenko beams Eshraghi, Iman; Dağ, Serkan (2018-01-15) A new domain-boundary element method is developed for elastodynamic analysis of functionally graded Timoshenko beams. Three governing partial differential equations of motion are derived by considering through-the-thickness variations of the physical properties. Weighted-residual forms are imposed utilizing the static fundamental solutions. These forms are then reduced to three integral equations containing domain integrals with time derivatives of unknown functions. Through domain discretization and shape ...
Computational elastodynamics of functionally graded thick-walled cylinders and annular coatings subjected to pressure shocks Abeidi, Abdelrahim; Dağ, Serkan (2022-12-01) A computational technique based on domain-boundary element method (D-BEM) is developed for elastodynamic analysis of functionally graded thick-walled cylinders and annular coatings subjected to pressure shock type of loadings. The formulation is built on the wave equation, which is derived in accordance with plane elastody-namics. Weighted residual statement for the wave equation is expressed by using the static fundamental solution as the weight function. Applying integration by parts and incorporating the...
Analytical Solutions To Elastic Functionally Graded Cylindrical And Spherical Pressure Vessels Eraslan, Ahmet Nedim (2015-10-01) Analytical solutions to earlier models by Chen and Lin [1] concerning elastic analysis of functionally graded cylindrical and spherical pressure vessels are obtained and presented.
Gold-tin eutectic bonding for hermetic packaging of MEMS devices with vertical feedthroughs Torunbalci, Mustafa Mert; Demir, Eyup Can; Donmez, Inci; Alper, Said Emre; Akın, Tayfun (2014-11-05) This paper presents a new method for wafer-level hermetic encapsulation of MEMS devices using low-temperature (280 to 300°C) Au-Sn eutectic bonding applied to the recently developed advanced MEMS (A-MEMS) process of the METU-MEMS Research Center, which uses an SOI cap wafer with vertical feedthroughs that does not need any complex via-refill or trench-refill process steps. The Au-Sn eutectic bonding process is achieved at 300°C with a bond pressure of 2 MPa by using a sealing alloy thickness less than 1.5 μ...
Thermal fracture analysis of orthotropic functionally graded materials using an equivalent domain integral approach Dağ, Serkan (2006-12-01) A new computational method based on the equivalent domain integral (EDI) is developed for mode I fracture analysis of orthotropic functionally graded materials (FGMs) subjected to thermal stresses. By using the constitutive relations of plane orthotropic thermoelasticity, generalized definition of the J-integral is converted to an equivalent domain integral to calculate the thermal stress intensity factor. In the formulation of the EDI approach, all the required thermomechanical properties are assumed to ha...

Citation Formats

A. Abeidi, “DOMAIN-BOUNDARY ELEMENT METHOD FOR ELASTODYNAMICS OF FUNCTIONALLY GRADED THICK-WALLED CYLINDERS AND ANNULLAR COATINGS,” Ph.D. - Doctoral Program, Middle East Technical University, 2022.