Comparison of regularizations of vortex sheet motion
نویسندگان
چکیده
This paper presents a numerical comparison of two regularizations of the Euler equations, namely, the vortex blob regularization and regularization by physical viscosity. The initial condition is a flat vortex sheet whose vorticity has been smoothed by convolution. The sheet rolls up into a vortex pair. We compute the frequency of oscillations in the core vorticity and scale it using results for a semi-infinite vortex sheet. The computations indicate that as the smoothing parameter δ and the viscosity ν decrease, the scaled frequency in the vortex blob solutions differs from the one in the Navier–Stokes solutions.
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