Journal of Tropical Oceanography ›› 2019, Vol. 38 ›› Issue (2): 13-19.doi: 10.11978/2018079CSTR: 32234.14.2018079

• Marine Hydrography • Previous Articles     Next Articles

Laboratory study on the effect of varying reef-flat width on wave transformation and wave-induced setup

Yu YAO1,2(), Tiancheng HE2, Zhengjiang TANG2, Changbo JIANG2,3   

  1. 1. Key Laboratory of Coastal Disasters and Defense of Ministry of Education, Hohai University, Nanjing 210098, China
    2. School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410004, China;
    3. Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410004, China
  • Received:2018-07-29 Revised:2018-11-05 Online:2019-03-20 Published:2019-04-15
  • Supported by:
    National Natural Science Foundation of China (51679014);Hunan Science and Technology Plan Program (2017RS3035);Open Foundation of Key Laboratory of Coastal Disasters and Defense of Ministry of Education (201602)

Abstract:

A series of laboratory experiments were carried out in a wave flume to study the influences of different reef-flat widths on wave transformation over reef coasts as well as wave-induced setup on reef flats. A series of incident irregular wave conditions were tested based on the idealized reef model with three reef-flat widths. Results show that as waves propagate across the reef, the swell height decays all the way, whereas the infragravity wave height increases gradually along the reef and reaches the maximum at the shoreline. Near the shoreline, the swell height decreases with increasing reef-flat width, but the variation of infragravity wave height with the reef-flat width is not obvious. The effect of varying reef-flat width on wave-induced setup over the reef flat is insignificant. The first resonant mode is identified on reef flat for the infragravity waves, and the level of resonant amplification near the shoreline is determined by the combined effect of reef-flat water depth, incident peak wave period and reef-flat width.

Key words: infragravity wave, wave-induced setup, reef-flat width, reef-flat resonance

CLC Number: 

  • P731.22