ID 320

An Experimental and Computational Study of a Single Diesel Droplet Impinging on a Dry Surface

 

Abstract:

This work presents experiments and computational simulations of a single diesel droplet impinging on a dry surface to provide a better understanding of the dynamic impingement process. The experimental work was carried out at various ambient conditions where a single diesel droplet was injected from a precision syringe pump at a specific volumetric flow rate, providing distinct impact Weber numbers. The effect of the surface temperature on the temporal evolution of the droplet spreading factor, dynamic contact angle, and contact line velocity was studied. The experimental study on the temporal evolution of the droplet-wall interaction was used to develop a dynamic contact angle model for computational simulations. Using an in-house multiphase flow solver, computational simulations of the single diesel droplet impingement were performed and compared to the experiments. The simulation results of the spreading factor, height ratio, and dynamic contact angle match well with the experimental values. The development of a dynamic contact angle model for diesel droplets enhances the ability to study diesel droplet impingement, an important factor in diesel fuel injection. With an accurate dynamic contact angle model, future studies can be performed at scales and velocities representative of the conditions present in internal combustion engines.