• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.4
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• pp.1-8
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• 1994

이 논문에서 우리는 발전하는 전단층의 2차원 Wave Mode에 대한 비선형 상호작용에 대한 문제를 다루었다. 총 위상각은 Wave Mode ij와 k$\ell$의 상응하는 에너지와 위상 상호작용을 조절한다. 그러므로 이 논문의 목적은 전단층에서 Lange-Scale 구조의 초기 위상각의 효과를 조사하고자 하는 것이다. 이 연구에서 우리는 Subharmonic의 존재는 전단층의 성장에 상당한 영향을 준다는 것을 알았고 Entrainment에서도 증가하는데 영향을 준다는 것을 알았다. 우리는 또한 Mean Flaw와 Fundamental의 다른 초기 위상각의 효과는 Subharmonic이 성장하는 먼 Downstream 영역에서 보여지기 시작한다는 것을 알았다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.3
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• pp.316-325
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• 1998

The objective of this study is to investigate the role of large-scale coherent structures in a spatially developing plane mixing layers. To achieve this, we have to look into the mutual interactions between three-dimensional large-scale coherent structures and the mean flow. Our attention will be focused on the energy exchange mechanism between the various modes, and the effects of the nonlinear evolution of the phases of the interacting modes. Linear stability of the three-dimensional viscous shear layer is formulated and solved as the basis for the solution of the nonlinear formulation based on the energy method. The importance of the initial conditions that may affect the evolution of the flow has been examined. It has been numerically calculated the nonlinear effects arising from the interactions among the three-dimensional large-scale coherent structures in a spatially developing plane mixing layers. The results of this study provide useful parametric information for the control of shear layer in practical applications in the mixing and transport augmentation.