K.V.Terletska, V.S.Maderich, I.A.Brovchenko, T.G.Talipova Incomplete self-similarities of in thermal waves of the second mode in the layer of separation |
Applied hydromechanics, Vol. 16 (88) ¹ 1, (2014) |
| According to the results of numerical experiments the analysis of the internal structure of the second mode wave for a wide wave amplitude and stratification range. It is shown that the most important characteristics that govern the dynamics of waves are local Froude number Frm, calculated as the ratio of the maximum local rate to the phase velocity of the waves, minimum Richardson number Rimin and the effective number Reynolds Reeff, defined as the ratio the product of the phase velocity of the waves and the wave amplitude a to kinematic viscosity. Depending on the parameter values Frm and Rimin three main classes of symmetric waves of the second mode propagating in the interface layer of thickness h between two homogeneous layers in deep water are identified: (a) the weakly nonlinear waves at Frm <1 , (b) stable strongly nonlinear waves that carry mass at Rimin>0.15 and Frm≈1.2, and (c) unstable strongly nonlinear waves at Rimin≤0.1. It was revealed incomplete self-similarity of waves at high Reynolds number Reeff. Wave damping occurs over time, so that the Richardson number is growing by self-similar dependence Rimin~(a/h)-1.25Reeff-1.25. |
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KEY WORDS: numerical modelling, internal waves of the second mode, incomplete similarity |
| TEXT LANGUAGE: Russian |