A Study of Drop Spreading Under the Effects of Temperature and Pressure by the Molecular Dynamics Simulation

• Main Authors: Lee Cho-Hsun, 李卓勳
• Other Authors: Hwang Chi-Chuan
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/42279891392093875503

碩士 === 中原大學 === 機械工程研究所 === 86 === The purpose of this paper is to study the spreading of liquid drops onsolid surfaces under the effects of temperature and pressure by using themethod of molecular dynamics simulation. The 12-6 Lennard-Jones model willbe taken to simulate the potential of liquid drops spreading on solid surfaces.In our physical model, we adopt the temperature-scaling model to keep thissystem in isothermal state by using the NVT ensemble. Then we use the Gear'sfive-order predictor-corrector method to calculate the positions and thevelosities of molecules. And the Verlet List Method is also used to economizethe calculation time.During the research, we are going to observe the behaviorof spreading of liquid drops on solid surfaces, and the final equilibrium stateof spreading for the whole system.In the meantime,we try to derive the relationbetween the radius-growth rate as well as its effect by regulating thetemperature and pressure of the system. In other way, we use three differentsizes of the liquid drops to simulate. So that can be fitted in the realsituation. Simulations show that the spreading rate is increased as thetemperature and pressure are upgraded, and the spreading radii varying withtime can be described by a general relation of R2(t) ~ at, which is in agreement with results obtained by previous investigators.Results also indicate the spreading rate is strongly related to the strength of the potential ratio between liquid and solid as well as its effect by changing the temperature and pressure of the system.