南海东北部深水海域大振幅内孤立波的数值模拟

Numerical Simulation and Research of SAR Signatures ofLager-amplitude Internal Solitary Waves in the Deep Sea in theNortheast South China SeaAbstractIn this paper,the simulation of propagation of the large-amplitude internal solitarywaves in the deep sea in the Northeast South China Sea is made on the basis ofcontinuous stratified oceanic model and by using the generalized K-dV(GK-dV)equation.Moreover,the simulation research of SAR signatures of the large-amplitude internalsolitary waves is made.In the ocean generally the background shear current and ocean stratification must betaken into the eigenvalue problem of nonlinear internal waves,but this takes somedifficulty for equation solution.In this paper,a numerical calculation method ofeigenvalue problem of nonlinear internal waves is presented on the basis of theThompson-Haskell's calculation method.It is perfectly solved the eigenvalue problem ofnonlinear internal waves on the basic of continuous stratified oceanic model.And it isused in the follows when solves the eigenvalue problem of internal solitary waves.Based on the works that precede,it uses the model,which is on the basis ofcontinuous stratified oceanic model and using the GK-dV equation,to simulation oflarge-amplitude internal solitary waves in the deep sea (the sea basin and the continentalslope area)in the Northeast South China Sea.And the model is used in two conditions:one is that the background current is composed of circulation and flood current,and theother is composed of circulation and ebb current.The impact of barotropic tidal currenton internal wave mode structure function (z),the nonlinearity coefficient a and thedispersion coefficient B of GK-dV equation,the phase speed c of long internal waves,as well as the amplitude and shape of internal solitary waves is considered.It is foundthat barotropic tidal current has a small effect on(z)and but has a great effect on aandc.The effect on a in the shallow sea is larger than that in the deep sea,but on c is