Abstract
Many researches have discussed a drop impingement behavior onto liquid surface under the condition with the same kind of fluid for both of drop and liquid free surface. The behaviors of free surface and a bubble entrainment in a drop impact are visualized using a high-speed video camera. The fluids for free surface and a drop are used same and different kind of fluids in the drop impact test. The experimental condition is changed by using several kind of fluids and various drop releasing height. The bubble entrainment condition using different fluids is not equal to that of same fluid though the results with same fluid correspond to the previous studies. The shape of free surface vicinity on the drop impact with bubble entrainment correspond to the dropping condition. The shape near the free surface is recognized by using non-dimensional number WeFr1/4.
