Abstract:

Large amplitude nonlinear oscillations of an axially symmetric water drop of 2.51-cm diameter, initial aspect ratio 3.4, with surfactant Triton X-100 of 0.5 mM, in zero gravity are studied by a boundary element method. Included in the analysis are surface-shear and dilatational viscos-ity, under the assumption that the shear viscosity of the bulk phase is small. Numerical simulations of the drop oscillations are in good agreement with the experimental results of drop oscillations measured in space during the second United States Microgravity Laboratory, USML-2. The evolution of the drop oscillations for both experiment and simulation is given. The simulation provides predictions for the values of both surface dilatational viscosity and shear viscosity of 0.20 sp and 0.10 sp, respectively. In addition, with the simulated data, the damping constants, frequencies, and decomposed oscillation modes are computed. [Work supported by NASA through JPL, Contract No. 958722.]