Spray generation a wave absorbing sea wall under s strong wind and transport process of spray in the leeward direction.
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||KYUSHU UNIVERSITY|
MATSUNAGA Nobuhiro Kyushu University Interdisciplinary Graduate School of Enginnering Sciences, Associate Professor, 大学院・総合理工学研究科, 助教授 (50157335)
HASHIDA Misao Nippon Bunnri University, Faculty of Enginnering, Professor, 工学部, 教授 (70131969)
SUGIHARA Yuji Kyushu University Interdisciplinary Graduate School of Enginnering Sciences, Res, 大学院・総合理工学研究科, 助手 (70243970)
|Project Period (FY)
1995 – 1996
Completed(Fiscal Year 1996)
|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1996 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1995 : ¥1,400,000 (Direct Cost : ¥1,400,000)
|Keywords||Coastal environments / Salt damege / Sea water spray / 沿岸海域環境 / 沿岸構造物 / 物質輸送|
Studies of 'Spray generation from a wave absorbing sea wall under a strong wind and transport process of spary in the leeward direction' have been made with the aid of a grant form the Ministry of Education, Science, Sports and Culture. The results are summarized as follows.
1.Spray generation and transport process from a wave absorbing sea wall.
2.Model experiments were carried out for a wave absorbing sea wall with a standard cross-section which is built at Beppu Port in Oita Prefecture.
1) Near the sea wall, the spray concentration is determined by the equilibrium between the advection of spray and its sedimentation. In a region far from the sea wall, the spray becomes very small and is in the equilibrium between its advection and diffusion.
2) A flow chart is obtained to estimate the spray concentration near a sea wall.
2.Transport process of spray above a beach model.
It is very important to understand the difference between the transport processes of spray above a natural beach and a beach protected by man-made structures. From such a point of view, the transport process of spray above a beach model was investigated experimentally.
1) In an offshore zone, the vertical profiles of spray quantity and spray concentration are uniform in the leeward direction. They are determined by the balance between the diffusion of spray and its sedimentation.
2) In a shallow region, the balance in an offshore zone is broken and the concentration decreases rapidly in the leeward direction.
3) Above the ground, the balance between the advection of spray and its diffusion is formed because no spray is supplied from the lower boundary and very small spray is transported.
Research Output (20results)