Prof. Guoxin Cao

Department of Mechanics & Engineering Science,

Peking University, Beijing 100871, China,

Caoguoxin@pku.edu.cn

In order to meet the requirement for the light-weight, small-volume and high-efficiency energy absorption system, new materials and structures need to be developed. Recently, a new high-performance nanoporous energy absorption system (NEAS) has attracted considerable research interests. The working mechanism of nanoporous energy absorption system (NEAS) under high speed impact loading condition are explored using molecular dynamics simulations and the effects of loading rate and tube size are also considered. The present NEAS is composed of single-walled carbon nanotube (CNT) segment and water molecules. The work done by the impact load can be converted into three parts: (I) water molecules potential change due to nano-confinement, (II) solid-liquid interaction energy and (III) the heat dissipated by the solid-liquid surface friction. We found that the change of water molecules potential gives the main contribution. In addition, the energy absorption density of NEAS is much higher than that of the conventional energy absorption materials, which decreases with the tube size and slightly increases with the impact loading rate. Furthermore, water molecules can transport through CNTs very fast under the high loading rate, thus NEAS can meet the requirement of a very low response time to prevent against the high speed impact load. Based on our simulations, NEAS can be a very promising candidate to protect against high speed loading.

Time: March 7th, 10:00-11:30

Location: Room 412，North Building Meng Minwei of Tsinghua University science and Technology Building