A piezoelectric mono-dispersed droplet generator was designed to study the deformation of droplets under the aerodynamic force by the high speed imaging system. The non-spherical drag model was established for the deformed water droplets. The process of water droplets impinging on the NACA23012 airfoil was simulated while the breakup model and splash model were introduced into Eulerian model. The simulated results were compared with the results from traditional model. It was found that the drag coefficient of water droplets increased because of the deformation. When the Reynolds number was larger than 500

water drag coefficient curve broke away with the spherical drag curve gradually and grew close to the disc drag coefficient curve. The droplet trajectory was affected because of the change of the drops drag properties

making the droplet follow with the air. The mass loss from splashing decreased the local collection coefficient on the airfoil

which was in good agreement with the experiment data.