Numerical study of successive droplets impingement on a solid surface with a pseudopotential based lattice Boltzmann model

Successive droplets impingement and coalescence on a solid surface is simulated to investigate the impact behavior and interaction dynamics among the impinging droplets with a specified offset ratio. A pseudopotential based lattice Boltzmann model is performed for the three-dimensional computations. The effects of surface wettability on two and a line of droplets impingement dynamics are investigated. Simulations show that spreading factor undergoes considerable undulation particularly in the out-of-phase collision mode with increasing the contact angle which leads to different morphology and footprint of merged droplets. Also, the effects of surface wettability on the uniformity of multiple droplets deposited line formation are investigated. The results show that the situations with increasing surface wettabilities and colliding in the in-phase collision mode are prefered to improve the uniform morphology during the line formation process.