Seminar: Harmonic oscillations around surface Ekman layer

Thời gian: 14:00 đến 16:00 Ngày 14/03/2025

Địa điểm: Phòng B102, VIASM

Báo cáo viên: Nguyễn Thiệu Huy, Hanoi University of Science and Technology

Tóm tắt: During his Fram expedition of 1893-1896 to reach the geographical North Pole, the Norwegian explorer Fridtjof Nansen had observed that icebergs tend to drift not in the direction of the prevailing wind but at an angle of 20^o - 40^o to the right. Then, Walfrid Ekman, who was still a student at that time, started to investigate the problem. Later, in 1905, Ekman published his theory of the Ekman spiral which explains the phenomenon in terms of the balance between frictional effects in the ocean and the Coriolis force, which arises from moving objects in a rotating environment, like planetary rotation. In this talk, we consider Navier-Stokes Equations in rotational framework around the surface Ekman layer and prove the existence and polynomial stability of a periodic solution to such equations under the action of a periodic external force. Furthermore, in case the external force is almost periodic, we also prove the existence and stability of an almost periodic solution to such a problem.