Characterizing dynamic behavior of carbon dioxide nano-jets using molecular dynamics simulation

• Published in: Applied physics. A, Materials science & processing Vol. 123; no. 12; pp. 1 - 10
• Main Authors: Huang, Pei-Hsing, Chou, Chuen-Shii, Hung, Shang-Chao, Jhan, Jhih-Wei
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2017; Springer Nature B.V
• Subjects: Applied physics; Carbon dioxide; Characterization and Evaluation of Materials; Computer simulation; Condensed Matter Physics; Cylinders; Design engineering; Extrusion; Injectors; Machines; Manufacturing; Materials science; Molecular dynamics; Nanotechnology; Optical and Electronic Materials; Outflow; Physics; Physics and Astronomy; Processes; Surfaces and Interfaces; Thin Films
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-017-1419-y

This paper reports on the use of molecular dynamics (MD) simulations to elucidate the dynamic behavior of CO 2 through a Graphene/Au(111) nano-injector. We investigated the effects of jet diameter ( d ), system temperature ( T ), and the extrusion velocity ( v ) of a graphite piston plate on the jet pattern, system pressure ( P ), and the number of molecules ( N m ) in the outflow. Simulation results show that the combined effects of high v and small d induced a larger jet angle, resulting in an increase in the number of CO 2 molecules attached to the surface of the outlet. Increasing d enhanced the formation of the T-junction molecular geometry of CO 2 molecules, due to the effects of electrostatic attraction between C (0.5888 e ) and O (− 0.2944 e ) of CO 2 , which caused the formation of larger agglomerations of CO 2 molecules in the vicinity of the nano-injector orifice in the final extrusion stage. The increase in P within the cylinder of the nano-injector was more pronounced during middle and final stages of extrusion, compared with the effects observed during the initial stages. Despite the fact that N m increased noticeably with an increase in T , the value of N m at d  = 1.5 nm and T  ≥ 300 K greatly exceeded that at d  = 1.0 nm and T  = 500 K, regardless of the value of v . The numerical simulations presented in this study could be helpful in the design of nano-injectors for a diversity of applications associated with engineering systems and biomedicine at the nano-scale. Graphical abstract