16 Oct. 2019
From 16th to 17th Oct. 2019, Dr. J. N. Reddy, the world-renowned expert of applied mechanics and distinguished professor of Texas A&M University, visited Zhejiang University and delivered two inspiring academic lectures.
On 16th, Dr. Reddy presented in Yuquan Campus an academic lecture entitled A Dual Mesh Finite Domain Method: A Marriage of Finite Element and Finite Volume Methods. Taking the potential theory problem as an example, Dr. Reddy first introduced the traditional finite element method and the finite volume method. By comparing the similarities and differences between the two methods, he proposed a new method, called dual-mesh finite domain method, by combining the advantages of the two existing methods. Numerical examples were presented to illustrate the methodology and accuracy compared to the finite element and finite volume solutions.
On 17th, Dr. Reddy made a second academic lecture in Zijingang Campus, which is entitled Efficient 7 and 12-Parameter Locking-Free Shell Finite Elements For Large Deformations Analysis of Structures. He discussed shell finite elements based on seven-parameter and twelve-parameter shell theories for large deformation analysis of composite shell structures. The seven-parameter shell element is based on a modified first-order shell theory using a seven-parameter expansion of the displacement field. The twelve-parameter shell element is developed using third-order thickness stretch kinematics. Both theories require the use of fully three-dimensional constitutive equations. The virtual work statement is integrated numerically through the shell thickness at each quadrature point of the mid-surface; hence no thin-shell approximations are imposed in the numerical implementation. The finite element coefficient matrices and force vectors are evaluated numerically using appropriate high-order Gauss-Legendre quadrature rules at the appropriate quadrature points of the element mid-surface. For laminated composite shells, a user prescribed vector field (defined at the nodes) tangent to the shell mid-surface is introduced. This discrete tangent vector allows for simple construction of the local bases associated with the principal orthotropic material directions of each lamina. As a result, one is free to employ skewed and/or arbitrarily curved elements in actual finite element simulations. Through the numerical simulation of carefully chosen benchmark problems, it was shown that the developed shell elements are insensitive to all forms of numerical locking and severe geometric distortions and predict very accurate displacement and stress fields.
The two lectures were warmly received by teachers and students from the related disciplines (such as mechanics, mechanical engineering, and civil engineering) of Zhejiang University. Dr. Reddy also shared his thoughts and experience in his life which have led to his great success in academic research.
Dr. Reddy is one of the top experts in the area of mechanics in the world. His early works on dual complementary variational principles and mathematical theories of finite element method have greatly promoted the constructions and applications of new finite element methods. His most well-known work is to propose a new model of high-order shear deformation theory for shell structures. It is a revolutionary innovation in the theoretical analysis of advanced materials structures, as well as in the design of actual composite structures. This work has stimulated a lot of follow-up researches, and has become one of the popular models for analysis of shell structures in various commercial software such as Abaqus. In the last decade, Dr. Reddy has been mainly engaged in the analysis of micro- and nano-scaled structures. He has developed a series of new analytical and numerical approaches, and proposed a number of new models of important physical significance, making the research in this field more mature and the gap between basic research and industrial practice disappear gradually.
Dr. Reddy is the author of a large number of journal papers and 21 books (several with second, third, and fourth editions) on energy principles, variational methods, plates and shells, composite materials, mechanics of solids, and the finite element method (linear and nonlinear) and its applications. As a result of his extensive publications of archival journal papers and books in wide range of topics in applied sciences and engineering, Dr. Reddy is one of the original top 100 ISI Highly Cited Researchers in Engineering around world with over 27,650 citations and h-index of 77 as per Web of Science; the number of citations is over 67,600 with h-index of 105 and i10-index of 540 (i.e., 540 papers are cited at least 10 times) as per Google Scholar.
Because of his outstanding scientific contribution and great academic influence, Dr. Reddy has received almost every important award in the field of mechanics (including Theodore von Kármán Medal, Raymond D. Mindlin Medal, Belytschko Medal, John von Neumann Medal, Prager Medal, Nathan M. Newmark Medal, IACM O.C. Zienkiewicz Award, etc.). He is not only a member of the National Academy of Engineering (USA), but also a foreign member of Brazilian National Academy of Engineering, Indian National Academy of Engineering, and Canadian Academy of Engineering. He has written more than 10 textbooks which had a tremendous impact on the teaching of mechanics. He was thus awarded the Archie Higdon Distinguished Educator Award by the American Society of Mechanical Engineers (ASME) in 1997 and the ASME Medal in 2016. He has been selected to be the recipient of this year of the most prestigious Timoshenko Medal, which is known as the “Nobel Prize in Mechanics”.
