Energy dissipation after single vortex reconnection in He II at different temperatures
V.A. Andryushchenko and L.P. Kondaurova
Институт теплофизики им. С.С. Кутателадзе СО РАН пр. ак. Лаврентьева, 1, г. Новосибирск, 630090, Россия
Национальный исследовательский университет «МЭИ», ул. Красноказарменная, 14, г. Москва, 111250, Россия
Received June 3, 2019, published online June 26, 2019
The dynamics of vortex loops from the moment of reconnection to their collapse was investigated. Numerical studies were carried out within the framework of the vortex line model at different temperatures and for various initial data. It is shown that at non-zero temperatures after the moment of reconnection, i.e., in the presence of large disturbances, an increased rate of dissipation of the total kinetic energy due to the mutual friction force is observed. The dissipation power increases with increasing temperature. The value of the vortex pulse modulus decays linearly, starting from the moment of reconnection, and also has a universal shape. Near the absolute zero at the chosen spatial resolution, a cascade of Kelvin waves is not observed, apparently this occurs on a smaller scale. The time dependences of the length of the vortex loops, the average curvature, the minimum distance between the disturbances are obtained.