Keisuke Nakayama, Tetsuya Shintani, Taro Kakinuma, Yasuyuki Maruya, Yoshinori Yonome, Mitsuaki Yonemoto, Isao Nakauchi


This paper describes the influence of surface waves on salt-wedge intrusion in terms of radiation stress. Radiation stress may increase salt-wedge intrusion when surface waves propagate up a river. This study thus aims to reveal the effect of radiation stress on the distance of salt-wedge intrusion by using fully nonlinear strongly dispersive internal wave equations and three-dimensional numerical computation model, Fantom3D. Fully nonlinear strongly dispersive internal wave model reveals the possibility that large radiation stress is induced near the river mouth and increases the distance of salt-wedge intrusion. Three-dimensional numerical model also demonstrates that there is a significant difference in the intrusion distance by taking into account radiation stress.


variable principle; radiation stress; salt-wedge intrusi

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