TY - JOUR
T1 - Response to "Comment on 'A mean field prediction of the asymptotic state of decaying 2D turbulence'" Phys. Fluids 10, 1237 (1998)
JF - Physics of Fluids
Y1 - 1998
A1 - Brands, H.
A1 - Stulemeyer, J.
A1 - Pasmanter, R. A.
A1 - Schep, T. J.
VL - 10
SN - 1070-6631
U5 - 66bc8fa44ec2b892b7e6db57ebe1ee68
ER -
TY - JOUR
T1 - Role of core losses in drift-vortex interactions
JF - Physical Review E
Y1 - 1997
A1 - Westerhof, E.
A1 - Rem, J.
A1 - Schep, T. J.
AB - Dipole drift vortices in the Hasegawa-Mima-Charney equation are studied by means of particle-in-cell (PIC) calculations. Apart from providing an efficient and accurate solution of the equations, PIC provides additional information about the fluid flow such as exchange of fluid between regions interior and exterior to the dipoles. Several cases of perturbed dipoles are studied with particular emphasis on the evolution of the fluid that is initially trapped inside the separatrix of the co-moving stream function of each unperturbed dipole. In particular, the effect of a finite tilt of the dipole axis is analyzed. Here, asymmetric losses from the two dipole halves are found to play a crucial role in the qualitative evolution of the dipole trajectory: dipoles initially moving in the unstable direction are found to reverse their average velocity perpendicular to the density gradient. Very large perturbations are obtained in dipole collisions. Here symmetry of the initial conditions plays an important role: collisions of aligned dipoles appear almost solitonlike, while for nonaligned dipoles the collision at least generates a tilt of the axes of the dipoles, but may also lead to a complete destruction of one of the poles. In all cases a significant loss of initially trapped fluid is demonstrated.
VL - 56
SN - 1063-651X
U5 - c98568933fed6bec691996f99c7362e4
ER -