ترغب بنشر مسار تعليمي؟ اضغط هنا

The number of traveling wave families in a running water with Coriolis force

219   0   0.0 ( 0 )
 نشر من قبل Hao Zhu
 تاريخ النشر 2020
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

In this paper, we study the number of traveling wave families near a shear flow $(u,0)$ under the influence of Coriolis force, where the traveling speeds lie outside the range of $u$. Let $beta$ be the Rossby number. If the flow $u$ has at least one critical point at which $u$ attains its minimal (resp. maximal) value, then a unique transitional $beta$ value exists in the positive (resp. negative) half-line such that the number of traveling wave families near $(u,0)$ changes suddenly from finite one to infinity when $beta$ passes through it. If $u$ has no such critical points, then the number is always finite for positive (resp. negative) $beta$ values. This is true for general shear flows under a technical assumption, and for flows in class $mathcal{K}^+$ unconditionally. The sudden change of the number of traveling wave families indicates that nonlinear dynamics around the shear flow is much richer than the non-rotating case, where no such traveling waves exist.



قيم البحث

اقرأ أيضاً

We consider the stability of periodic gravity free-surface water waves traveling downstream at a constant speed over a shear flow of finite depth. In case the free surface is flat, a sharp criterion of linear instability is established for a general class of shear flows with inflection points and the maximal unstable wave number is found. Comparison to the rigid-wall setting testifies that free surface has a destabilizing effect. For a class of unstable shear flows, the bifurcation of nontrivial periodic traveling waves of small-amplitude is demonstrated at any wave number. We show the linear instability of small nontrivial waves bifurcated at an unstable wave number of the background shear flow. The proof uses a new formulation of the linearized water-wave problem and a perturbation argument. An example of the background shear flow of unstable small-amplitude periodic traveling waves is constructed for an arbitrary vorticity strength and for an arbitrary depth, illustrating that vorticity has a subtle influence on the stability of water waves.
Let $(X,g)$ be a compact manifold with conic singularities. Taking $Delta_g$ to be the Friedrichs extension of the Laplace-Beltrami operator, we examine the singularities of the trace of the half-wave group $e^{- i t sqrt{ smash[b]{Delta_g}}}$ arisin g from strictly diffractive closed geodesics. Under a generic nonconjugacy assumption, we compute the principal amplitude of these singularities in terms of invariants associated to the geodesic and data from the cone point. This generalizes the classical theorem of Duistermaat-Guillemin on smooth manifolds and a theorem of Hillairet on flat surfaces with cone points.
We study traveling wave solutions of the nonlinear variational wave equation. In particular, we show how to obtain global, bounded, weak traveling wave solutions from local, classical ones. The resulting waves consist of monotone and constant segment s, glued together at points where at least one one-sided derivative is unbounded. Applying the method of proof to the Camassa--Holm equation, we recover some well-known results on its traveling wave solutions.
169 - Dawit Denu , Sedar Ngoma , 2019
We consider an epidemic model with direct transmission given by a system of nonlinear partial differential equations and study the existence of traveling wave solutions. When the basic reproductive number of the considered model is less than one, we show that there is no nontrivial traveling wave solution. On the other hand, when the basic reproductive number is greater than one, we prove that there is a minimum wave speed $c^*$ such that the system has a traveling wave solution with speed $c$ connecting both equilibrium points for any $cge c^*$. Moreover, under suitable assumption on the diffusion rates, we show that there is no traveling wave solution with speed less than $c^*$. We conclude with numerical simulations to illustrate our findings. The numerical experiments supports the validity of our theoretical results.
We describe traveling waves in a basic model for three-dimensional water-wave dynamics in the weakly nonlinear long-wave regime. Small solutions that are periodic in the direction of translation (or orthogonal to it) form an infinite-dimensional fami ly. We characterize these solutions through spatial dynamics, by reducing a linearly ill-posed mixed-type initial-value problem to a center manifold of infinite dimension and codimension. A unique global solution exists for arbitrary small initial data for the two-component bottom velocity, specified along a single line in the direction of translation (or orthogonal to it). A dispersive, nonlocal, nonlinear wave equation governs the spatial evolution of bottom velocity.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا