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Molecular Level Understanding of Chemical Erosion on Graphite Surface using Molecular Dynamics Simulations

분자동역학을 이용한 그래파이트 표면에서의 화학적 삭마현상에 관한 분자 수준의 이해

  • Murugesan, Ramki (Graduate School of Mechanical and Aerospace Engineering, Gyeongsang National University) ;
  • Park, Gyoung Lark (Graduate School of Mechanical and Aerospace Engineering, Gyeongsang National University) ;
  • Levitas, Valery I. (Department of Aerospace Engineering, Iowa State University) ;
  • Yang, Heesung (Research Division, Seyeon Engineering and System) ;
  • Park, Jae Hyun (Department of Aerospace and Software Engineering and Research Center for Aircraft Parts Technology, Gyeongsang National University) ;
  • Ha, Dongsung (The 4th R&D Institute, Agency for Defense Development)
  • Received : 2015.09.25
  • Accepted : 2015.11.10
  • Published : 2015.12.01

Abstract

We present a microscopic understanding of the chemical erosion due to combustion product on the nozzle throat using molecular dynamics simulations. The present erosion process consists of molecule-addition step and equilibrium step. First, either $CO_2$ or $H_2O$ are introduced into the system with high velocity to provoke the collision with graphite surface. Then, the equilibrium simulation is followed. The collision-included dissociation and its influence on the erosion is emphasized and the present molecular observations are compared with the macroscopic chemical reaction model.

본 연구에서는 고온/고압의 연소가스에 의해 야기되는 노즐목 삭마현상의 분자수준 메커니즘을 분자동역학 시뮬레이션을 이용하여 관찰한다. 노즐목은 두 개의 그래핀으로 구성된 그래파이트로 모델링하고 분자동역학 시뮬레이션은 충분한 속도를 가지고 그래파이트에 충돌하는 $H_2O$ 분자와 $CO_2$ 분자가 지속적으로 생성되는 과정과 평형상태의 시뮬레이션으로 구성된다. 반응을 모사할 수 있는 ReaxFF 포텐셜을 사용하며, 충돌에 의해 야기되는 $H_2O$$CO_2$ 분자의 해리와 화학적 삭마와의 관계에 중점을 두고 관찰하고자 하며, 거시적인 관찰결과들과 비교하고자 한다.

Keywords

References

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