The study on the bottom friction and the breaking coefficient for typhoon waves in radial sand ridges—the Lanshayang Channel as an example
-
摘要: 受到复杂地貌、底质、水动力的相互影响,辐射沙脊群的台风浪呈现中低潮阶段波高较小,高潮阶段波高较大的特征。一般而言,粉沙淤泥底质的阻尼效应,砂质海床的底摩阻和波浪破碎对研究区域的波浪传播有较大影响。受低能波影响,近底粉沙淤泥层形成并随波浪运动至浅水区域,因此,阻尼效应在中、低潮位较为普遍,较大Collins系数(1左右)可用于计算中低潮位阶段阻尼效应导致的波能损耗。但受高能波作用,底质起动、悬扬,阻尼效应逐渐消失。籍此,提出随水位升降变Collins系数法,并植入SWAN模拟辐射沙脊群烂沙洋水道的台风浪过程,同时利用“9711”台风期间的波浪观测数据进行验证。验证结果显示,随水位升降变Collins系数法可较为准确地模拟辐射沙脊群期间的台风浪,同时,破波系数0.78适用于计算辐射沙脊群这种缓坡宽潮滩的台风浪。Abstract: Owing to the interactions among the complex terrain, bottom materials, and the complicate hydrodynamics, typhoon waves show special characteristics as big waves appeared at the high water level (HWL) and small waves emerged at low and middle water levels (LWL and MWL) in radial sand ridges (RSR). It is assumed that the mud damping, sandy bed friction and wave breaking effects have a great influence on the typhoon wave propagation in this area. Under the low wave energy, a mud layer will form and transport into the shallow area, thus the mud damping effects dominate at the LWL and the MWL. And high Collins coefficient (c around 1) can be applied to computing the damping effects at the LWL and the MWL. But under the high wave energy, the bottom sediment will be stirred and suspended, and then the damping effects disappear at the HWL. Thus the varying Collins coefficient with the water level method (VCWL) is implemented into the SWAN to model the typhoon wave process in the Lanshayang Channel (LSYC) of the RSR, the observed wave data under “Winnie” (“9711”) typhoon was used as validation. The results show that the typhoon wave in the RSR area is able to be simulated by the VCWL method concisely, and a constant wave breaking coefficient (γ) equaling 0.78 is better for the RSR where wide tidal flats and gentle bed slopes exist.
-
Key words:
- typhoon wave
-
Battjes J, Janssen J P F M. 1978. Energy loss and set-up due to breaking of random waves. In: Proceeding of 16th International Conference on Coastal Engineering. New York: ASCE, 569-587 Battjes J A, Stive M J F. 1985. Calibration and verification of a dissipation model for random breaking waves. Journal of Geophysical Research, 90 (C5): 9159-9167 Booij N, Ris R C, Holthuijsen L H. 1999. A third-generation wave model for coastal regions, Part I. Model description and validation. Journal of Geophysical Research, 104 (C4): 7649-7666 Chen Kefeng, Wang Yanhong, Lu Peidong, et al. 2009. Effects of coastline changes on tide system of yellow sea off Jiangsu Coast, China. China Ocean Engineering, 23(4): 741-750 Choi J, Sung B Y. 2011. Numerical simulation of nearshore circulation on field topography under random wave environment. Coastal Engineering, 58(5): 395-408 Collins J I. 1972. Prediction of shallow water spectra, Journal of Geophysical Research, 77 (15): 2693-2707 Dean R G, Dalrymlple R A. 2002. Coastal Processes with Engineering Applications. London: Cambridge University Press, 282-285 Deltares. 2011. Delft-Flow User Manual (version 3.15). Delft: Deltares DHI. 2011. Mike 21 and Mike 3 Flow Model FM Hydrodynamic and Transport Module Sciencetific Documentation. Hørsholm: DHI Elgar S, Raubenheimer B. 2008. Wave dissipation by muddy seafloors. Geophysical Research Letters, 35: L07611, doi:10.1029/ 2008GL033245 Feng Weibing. 2003. The Design Wave Elements for the Land-island Passage Project of the Yangkou Port of Nantong Harbor (in Chinese). Nanjing: Hohai University: 24-25 Gallagher E L, Elgar S, Guza R T. 1998. Observations of sand bar evolution on a natural beach. Journal of Geophysical Research, 103(C2): 3203-3215 Goda Y. 2004. A 2-D random wave transformation model with gradational breaker index. Coastal Engineering Journal, 46(1): 1-38 Gong Chong Zhun, Dai Gonghu. 1983. Mathematical model for wave deformation in shoaling water and determination of bottom friction of silt beach. Ocean Engineering (in Chinese), 03: 21-33 Gratiot N, Gardel A, Anth ony E J. 2007. Trade-wind waves and mud dynamics on the French Guiana coast, South America: input from ERA-40 wave data and field investigations. Marine Geology, 236(1-2): 15-26 Holland K, Todd S B, Vinzon L J C. 2009. A field study of coastal dynamics on a muddy coast offshore of Cassino beach, Brazil. Continental Shelf Research, 29(3): 503-514 Holthuijsen L H, Herman A, Booij N. 2003. Phase-decoupled refraction- diffraction for spectral wave models. Coastal Engineering, 49(4): 291-305 Kaminsky G M, Kraus N C. 1993. Evaluation of depth-limited wave breaking criteria. Proceedings of the 2nd International Symposium on Ocean Wave Measurement and Analysis, New Orleans, 180-193 Kim B O. 2003. Tidal modulation of storm waves on a macrotidal flat in the Yellow Sea. Estuarine, Coastal and Shelf Science, 57(3): 411-420 Kranenburg W M, Winterwerp W, de Boer J, et al. 2011. SWAN-Mud: Engineering model for mud-induced wave damping. Journal of Hydraulic Engineering, 137(9): 959-975 Le Hir P, Roberts W, Cazaillet O, et al. 2000. Characterization of intertidal flat hydrodynamics. Continent Shelf Research, 20(12-13): 1433-1459 Nelson R, 1997. Height limits in top down and bottom up wave environments. Coastal Engineering, 32(2-3): 247-254 Padilla-Hernandez R, Monbaliu J. 2001. Energy balance of wind wave as a function of the bottom friction formulation. Coastal Engineering, 43(2): 131-148 Pereira P S, Calliari L J, Holman R, et al. Video and field observations of wave attenuation in a muddy surf zone. Marine Geology, 279 (1-4): 210-221 Ris R, Booij N, Holthuijsen L. 1999. A third-generation wave model for coastal regions: Part II. Verification. J Geo Res, 104(C4): 7649- 7666 Ruessink B G, Walstra D J R, Southgate H N. 2003. Calibration and verification of a parametric wave model on barred beaches. Coastal Engineering, 48(3): 139-149 Sheremeta A, Mehta A J, Liu B, et al. 2005. Wave-sediment interaction on a muddy inner shelf during Hurricane Claudette. Estuarine, Coastal and Shelf Science, 63(1-2): 225-233 The SWAN team. 2011. SWAN User Manual (version 40.85). Delft: Delft University of Technology TIWTE, 2005. The Study of the Engineering Stability of the Yangkou Port of Nantong Harbor(in Chinese), Tianjin: TIWTE, 34-36 Weggel J R, 1972. Maximum breaker height, Journal of Waterways Harbors. Coastal Engineering Division 98(WW4), 529-548 Winterwerp J C, de Boer Gerben J, Greeuw Gert, et al. 2012. Mud-induced wave damping and wave-induced liquefaction, Coast Engineering, 64: 102-112
点击查看大图
计量
- 文章访问数: 1378
- HTML全文浏览量: 47
- PDF下载量: 1883
- 被引次数: 0