Study on Calculation Method for Droplet Drag Coeffient Based on Dynamic Simulation and P Control

Droplet drag coefficient is the key factor which affects the droplet behavior. And there is no mature and general drag correlation for droplets. The present work proposed a new approach to calculate the droplet drag coefficient: the single droplet motion in the uniform flow is simulated dynamically. By adding the body force source item to the momentum equation, the position of the droplet centroid is controlled leading to its approximative simple harmonic motion. The droplet drag coefficient is estimated by analyzing its position change. The present approach was realized by using VOF method to simulate the droplet-gas two-phase flow and validated by several example cases. Results showed that compared with the efficient PID control method, the present approach is more convenient to select the control parameter and even more efficient in the calculation.