Abstract:
When the small scale unstable flows are excited by disturbance, they absorb energy from the basic flow field, a large scale movement pattern will arise, that is, the typhoon or the soliton will form. The forces include those related with dissipation, dispersion, advection or convection,and when all these forces come to an equilibrium, the corresponding movement pattern will be stable over a long time. With respect to the helical structure, we can investigate its similar dynamics in terms of the local energy. Theoretical analyses and simulation experiments about double typhoons by means of a large-scale geophysical fluid annulus, as well as numerical experiments (which will be carried out) may solve the following problem: whether the typhoon can be seen as a three-dimensional large scale helical soliton. It is a new idea, which is, therefore, helpful for the understanding of the formation mechanism and the dynamic characteristics of typhoon and soliton, and it is also a new research approach to combine the two aspects of the methodology.