Simulation of Rayleigh-Taylor Flows Using Vortex Blobs
نویسنده
چکیده
An mvtscrd boundary-Integral method 1s moddied m order to study the smgle-scale Raylergh-Taylor mstabthty for arbitrary Atwood number. The pnmary modificatron uses vortex blobs to smooth the Green’s functton and suppress a timte trme smgulartty in the curvature. Additronal moddicatrons to earher codes such as usmg second-order central drfferences along the Interface to accommodate spikes m the vorttctty and spreadmg the nodes evenly along the Interface to suppress clustering of nodes are destgned to mamtam resolutron and accuracy To achteve second-order accuracy in ttme when the nodes are spread, an extra predtctor step IS needed that shafts the nodes before the vartables are advanced The method successfully follows the development of a smgle mode to states wtth asymptotrc velocttres for the bubble and spoke that depend on the Atwood number and are Independent of the blob srze Inctprent droplet formatton IS observed ‘
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