Investigation the Characteristics of Unstable Binary Droplet Collision with High Speed

A new collision model was put forward by Munnannur, which can be used to predict characteristics of unstable binary droplet collisions. However, the energy dissipation coefficient and breakup parameter in original model were unchanged, which cut down the prediction accuracy for the length and volume of ligament formed by the collision. Based on the experimental results of Grenn, the energy dissipation coefficient and breakup parameter are revised to consider the influence of different impact parameter to improve the prediction accuracy. Furthermore, the characteristics of unstable collision of diesel droplets are discussed. The results show that the volume of separation ligament is dominated by the energy dissipation under small impact parameter while the volume of separation ligament is controlled by the volume fraction in the interaction region. The volume and length of the separated ligament increase with the increasing of Weber number, and also increase with the increasing of impact parameter firstly. After the respective peaks are reached, the volume and length of the separated ligament reduce though the impact parameter continues to increase.