PyCAC: The concurrent atomistic-continuum simulation environment

Journal of Materials Research - Tập 33 - Trang 857-871 - 2018
Shuozhi Xu1, Thomas G. Payne2, Hao Chen3, Yongchao Liu4, Liming Xiong3, Youping Chen5, David L. McDowell2,6
1California NanoSystems Institute, University of California, Santa Barbara, Santa Barbara, USA
2School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, USA
3Department of Aerospace Engineering, Iowa State University, Ames, USA
4School of Computational Science and Engineering, Georgia Institute of Technology, Atlanta, USA
5Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, USA
6GWW School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, USA

Tóm tắt

We present a novel distributed-memory parallel implementation of the concurrent atomistic-continuum (CAC) method. Written mostly in Fortran 2008 and wrapped with a Python scripting interface, the CAC simulator in PyCAC runs in parallel using Message Passing Interface with a spatial decomposition algorithm. Built upon the underlying Fortran code, the Python interface provides a robust and versatile way for users to build system configurations, run CAC simulations, and analyze results. In this paper, following a brief introduction to the theoretical background of the CAC method, we discuss the serial algorithms of dynamic, quasistatic, and hybrid CAC, along with some programming techniques used in the code. We then illustrate the parallel algorithm, quantify the parallel scalability, and discuss some software specifications of PyCAC; more information can be found in the PyCAC user’s manual that is hosted on http://www.pycac.org .

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