Unsteady motion of an initially stretched ligament in another immiscible fluid is studied numerically for the flow dominated by both inertia and viscosity. Numerical simulations were conducted using an axisymmetric version of a Front-Tracking / Finite Difference code. The ranges of the non-dimensional numbers are: 4.2 × 10−3 < OhD < 4.2 × 10−1 and 10−2 < μˆ < 10, where OhD is the Ohnesorge number based on the ligament (OhD = μD / 2a0ρDσ and μˆ is the viscosity ratio (μˆ = μDC). The tip of the ligament retracts due to the non-uniformness of the capillary force, and a bulb forms. Simulation results show that there are two different modes: i) the bulb pinches off and the rest of the ligament also breaks up into drops, and ii) the bulb moves toward the midsection of the ligament and the ligament becomes a spherical drop. The former mode is observed when the retraction takes enough time for capillary waves to grow. The latter mode takes place when the growth of capillary waves is slow relative to the retraction speed.

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