Numerical Analysis of Structures of Revolution using Universal Matrices Approach
Keywords:
Stiffness matrix, explicit formulation, closed-form, universal matrix, axisymmetric triangular elementsAbstract
Stress and displacement analysis of structures of revolution under axisymmetric loading is of considerable interest in engineering. Many practical problems can be idealized as an axisymmetric case, which simplifies the analysis and reduces the computational work. The axisymmetric triangular element is commonly used for modeling these cases. This paper proposes a method of generating stiffness matrix for the axisymmetric triangular element using universal matrices instead of numerical integration. The computation time of the proposed method was compared against the Gaussian numerical integration. The CPU time ratio for the 3-node element was 1:1.56, 1:1.79, and 1:1.89 for the proposed method against 1-point, 3-points, and 4-points Gaussian numerical integration respectively. The accuracy of the proposed method was 0.012% against the exact integration method. The 1-point, 3-points, and 4-points Gaussian numerical integration have an error of 0.059%, 0.001%, and 0.0006% respectively. Nodal displacements from this method were compared against the results of some commercially available finite element packages. The proposed method has a deviation of 0.44% from the theoretical values, while ABAQUS, ANSYS, and Optistruct has a deviation of 1.26%, 1.29%, and 1.44% respectively using the default number of integration points provided by the packages.
References
Abdullahi, H. S. (2015). Time efficiency analysis and error estimation in generating element stiffness matrices of axisymmetric plane triangular elements using universal matrix method. Department of Mechanical Engineering, SRM University, Chennai, India.
ANSYS. (2013). ANSYS Mechanical APDL Theory Reference, ANSYS Inc.pp. 1–909. Available at: www.ansys.com.
Chandrupatla, T. R. and Belegundu, A. (2001). Introduction to Finite Elements in Engineering. Prentice Hall, Upper Saddle River, New Jersey.
Cui, D. and Xu, Y. M. (2013). Finite element analysis in engineering. Beihang University Press, Beijing, China.
Gill, S. (1970). The stress analysis of pressure vessels and pressure vessel components. Pergamon Press.
Huttton, D. V. (2004). Fundamentals of Finite Element Analysis. McGraw-Hill.
Jeyakarthikeyan, P. V.; G. Subramanian and R. Yogeshwaran. (2017). An alternate stable midpoint quadrature to improve the element stiffness matrix of quadrilaterals for application of functionally graded materials (FGM), Computers & Structures, 178:71–87. doi: 10.1016/j.compstruc.2016.10.008.
Jeyakarthikeyan, P. V.; R. Yogeshwaran and H. S. Abdullahi. (2015). Time efficiency and error estimation in generating element stiffness matrices of plane triangular elements using Universal Matrix Method and Gauss-Quadrature, Ain Shams Engineering Journal, 9 (4): 965-972.
McCaslin, S. E.; P. S. Shiakolas, B. H. Dennis, and K. L. Lawrence. (2012). Closed-form stiffness matrices for higher order tetrahedral finite elements, Advances in Engineering Software, 44(1):75–79.
Pachpor, P. D.; N. D. Mittal, L. N. Gupla, and N. V. Deshpande. (2011). Finite element analysis and comparison of castellated & cellular beam, Advanced Materials Research, 264–265(1):649–699. doi: 10.4028/www.scientific.net/AMR.264-265.694.
Subramanian, G. and Bose, C. J. (1982). Convenient generation of stiffness matrices for the family of plane triangular elements, Computers and Structures, 15(1): 85–89. doi: 10.1016/0045-7949(82)90036-0.
Videla, L.; T. Baloa, D. V. Griffiths and M. Cerrolaza. (2008). Exact integration of the stiffness matrix of an 8-node plane elastic finite element by symbolic computation, Numerical Methods for Partial Differential Equations, 24(1):249–261.
Wilson, E. L. (1965). Structural analysis of axisymmetric solids. American Institute of Aeronautics and Astronautics Journal, 3(12): 2269–2274. doi: 10.2514/3.3356.
Zhou, C. E. and Vecchio, F. J. (2006). Closed-Form Stiffness Matrix for the Four-Node Quadrilateral Element with a Fully Populated Material Stiffness, Journal of Engineering Mechanics, 132(12): 1392–1395. doi: 10.1061/(ASCE)0733-9399(2006)132:12(1392).
Zienkiewicz, O. C.; R. L. Taylor, and D. Fox. (2013). The Finite Element Method for Solid and Structural Mechanics, 7th Ed., Butterworth-Heinemann, USA.
Zienkiewicz, O. C.; R. L. Taylor, and P. Nithiarasu. (2014). The Finite Element Method for Fluid Dynamics, 7th Ed., Butterworth-Heinemann, USA.
Zienkiewicz, O. C., Taylor, R. L. and Taylor, R. L. (2005). The Finite Element Method for Solid and Structural Mechanics, Elsevier, Oxford, UK.
Downloads
Published
Issue
Section
License
In accordance with the Copyright Act of 1976, which became effective January 1, 1978, the following statement signed by each author must accompany the manuscript submitted: "I, the undersigned author, transfer all copyright ownership of the manuscript referenced above to the Nigerian Journal of Technological Development, in the event the work is published. I warrant that the article is original, does not infringe upon any copyright or other proprietary right of any third party, is not under consideration by another journal, and has not been published previously. I have reviewed and approve the submitted version of the manuscript and agree to its publication in the Nigerian Journal of Technological Development." A copyright transfer form should be downloaded from the NJTD Website ( http://njtd.com.ng/index.php/njtd). Author(s) will be consulted, whenever possible, regarding republication of material. All authors must have access to the data presented and the authors and sponsor (if applicable) must agree to share original data with the editor if requested.