Dr. Li Pei, born in 1991, completed his bachelor and master degrees of Mechanical Engineering at Xi'an Jiaotong University, China, in 2012 and 2015 respectively. After that, he went to the National Unversity of Singapore (NUS) for his Ph.D. research, i.e. response of anisotropic polymeric foam to impact, under direction of Prof. Victor P. W. Shim, funded by NUS Research Scholarship. In August of 2019, he joined the research group of Prof. Vincent B. C. Tan and Prof. T. E. Tay at NUS as a Research Fellow, focusing on multiscale modelling of heterogeneous materials. As of 1st, May, 2020, Dr. Li started as an assistant professor in the Group of Production Technology & Group of Elastomer Technology and Engineering, Faculty of Engineering Technology, at the University of Twente.
Dr. Li's research interest includes but not limits to multiscale analysis of polymer composites, dynamic response of polymeric cellular materials, continuum consitutive modelling of polymeric heterogeneous materials, multiscale modelling of 3D printed cellular materials.
Multiscale analysis has been a significant demand for investigation into many materials, especially those consist of more than one type of phase, such as polymer composites comprising matrix and fillers, and those display micro-scale or meso-scale structures like polymer foams. Studying these materials requires an accurate description of their macro-scale response as well as a good understanding of their micro-scale deformation mechanism. A macro-scale model describing their continuum behaviour is valuable to estimate the mechanical performance of these materials in their actual applications, while the micro-scale mechanism plays an essential role in determining the macro-scale behaviour, and thus can be used to guide and optimize the design and manufacturing of these materials. Generally, there are two approaches for multiscale analysis:
1. The traditional approach of multiscale analysis is to establish a model for each scale seperately. For instance, at micro-scale, a unit cell model is built and further assembled to establish a meso-scale representative volume element (RVE). Simulation results obtained via the RVE are valuable in analysing the micro-scale deformation mechanism of materials, and these results can also be homogenised to derive effective properties at macro-scale. For macro-scale analysis of these materials, another continuum model is established by assuming that the material can be treated as a continua since the size of its unit cell is much smaller than the scale simulated. Continuum constitutive modelling of mechanical anisotropy is required for the macro-scale analysis, because materials including polymer composites and cellular materials exhibit obvious direction-dependence in their macro-scale response.
2. Another approach is concurrent multiscale modelling. It means that modelling of the material at different scales is performed simultaneously. This requires a good knowledge about computational mechanics, such as the theory of finite element square method, mean field method and coarsen graining method. The general idea of these methods is to directly incorporate micro-scale unit cell models or RVEs into a macro-scale model, and thus simulations at micro-scale and macro-scale can be completed at the same time. Concurrent multiscale modelling is promising to reveal the real-time cross-scale interaction in the materials mentioned above.
 Pei Li, V.P.W. Shim*, Y.B. Guo. "Dynamic deformation of anisotropic cellular material – from a microstructural to a continuum perspective", invited report, Nov. 2019, Beijing Institute of Technology, Beijing, China.
 Pei Li, V.P.W. Shim*, Y.B. Guo. "Response of anisotropic polymeric foam to impact", Mar. 2019, Sixth International Symposium on Explosion, Shock wave and High-strain rate Phenomena, Puducherry, India.
 Pei Li, V.P.W. Shim*, Y.B. Guo. "Modelling impact on anisotropic foam — A cell assembly approach ", invited report, Oct. 2018, Beijing Institute of Technology, Beijing, China.
 Pei Li, Y.B. Guo, G.F. Gao, V.P.W. Shim*. "Structural cell assembly model for impact on anisotropic foam". May 2018, Conference: International conference on impact loading of structures and materials, Xi'an, China.
 Guangfa Gao, P. Li, Y.B. Guo, V.P.W. Shim*. "Modeling microstructure of solid foam using random Kelvin open-cells – Influence of boundary parameters and cell strut cross-section". July 2017, The 8th International Conference on Computational Methods, Guilin, China.
 Victor P.W. Shim, Y.B. Guo, J.H. Chen, G.F. Gao, P. Li. "Dynamic Crushing of Anisotropic Polymeric Foam – Effects of Loading Direction and Strain Rate". May, 2016. Conference: International Conference on Impact loading of Structures and Materials. Turin, Italy.