%0 Journal Article %A Deshpande, S. S. %A Trujillo, Mario F. %A Kim, S. %D 2013 %I Begell House %K Rayleigh-Plateau mechanism, temporal instability, alternative fuels, OpenFOAM %N 12 %P 1167-1195 %R 10.1615/AtomizSpr.2013007672 %T COMPUTATIONAL STUDY OF FLUID PROPERTY EFFECTS ON THE CAPILLARY BREAKUP OF A LIGAMENT %U https://www.dl.begellhouse.com/journals/6a7c7e10642258cc,678beccc06b09526,3978bcc813b8a726.html %V 23 %X The creation of droplets in high-Weber-number liquid jets is preceded almost universally by the breakup of much smaller liquid ligaments according to visualizations provided by previous experimental and computational studies. In this work, this ligament breakup process is idealized as the Rayleigh-Plateau mechanism [Rayleigh, Proc. Roy. Soc. London, 1879], and it is used to study fuel property effects on various breakup characteristics. The fuels considered correspond to the traditional JP-5 and diesel fuels and their potential renewable substitutes, as well as a single species fuel, hexene, which represents an extreme in the fuel property range. An algebraic volume-of-fluid solver is employed to simulate the Raleigh-Plateau mechanism using 3D simulations. The solver is compared to the instability growth rate from theoretical predictions and previous numerical simulations, as well as droplet sizes reported in experiments, yielding good agreement. Results show that breakup times increase with increasing Ohnesorge number (Oh =µl/√(σρlRo)), and exhibit a strong demarcation point occurring at Oh = 0.1. This point is interpreted as representing a boundary between the viscous and inviscid domains occurring in the dynamics governing the last stages of ligament deformation prior to pinch off. This boundary point also characterizes satellite drop sizes, where for Oh > 0.1, these satellite droplets show a noticeable sensitivity to the Ohnesorge number, while for Oh < 0.1 this sensitivity is weak. Additionally, a prediction for break-up time is proposed, tbreak,M = (1/ωv) ln(1.87Roo), which matches the simulation data for all fuels to within 8%. It is also observed that the length of the liquid bridge, which characterizes the central section of the domain in the last stage of ligament deformation, is approximately constant for all fuels, and is equal to 5Ro . Lastly, a Fourier decomposition is performed to characterize ligament shape evolution for all fuels. %8 2013-11-26