The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary c...The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary condition. However, contact angle is changed according to contact line velocity and time. Hence, for accurate simulation, dynamic contact angle which has various values as time elapsed is adopted. In the present study, the numerical analysis is performed on the droplet spreading phenomena considering dynamic contact angle function which is obtained from single droplet spreading experiment on the flat and bare surface. The CIP (cubic interpolated pseudo-particle) method by Yabe is used for analysis of interface between liquid and gas phases. The numerical results considering contact angle function which newly modeled as time and contact angle are compared with numerical results considering Hoffman's function and experimental data for range of Weber number which are 4.427 and 11.334. In contrast of numerical result considering Hoffman's function, the numerical result shows good agreement with experimental data as time elapsed in contact angle evolution, deformation of droplet spreading radius and height. Indeed, overall, the results display the increasing maximum spreading radius and the decreasing height as Weber numbers increased.展开更多
文摘The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary condition. However, contact angle is changed according to contact line velocity and time. Hence, for accurate simulation, dynamic contact angle which has various values as time elapsed is adopted. In the present study, the numerical analysis is performed on the droplet spreading phenomena considering dynamic contact angle function which is obtained from single droplet spreading experiment on the flat and bare surface. The CIP (cubic interpolated pseudo-particle) method by Yabe is used for analysis of interface between liquid and gas phases. The numerical results considering contact angle function which newly modeled as time and contact angle are compared with numerical results considering Hoffman's function and experimental data for range of Weber number which are 4.427 and 11.334. In contrast of numerical result considering Hoffman's function, the numerical result shows good agreement with experimental data as time elapsed in contact angle evolution, deformation of droplet spreading radius and height. Indeed, overall, the results display the increasing maximum spreading radius and the decreasing height as Weber numbers increased.