A numerical study of tsunami wave run-up and impact on coastal cliffs using a CIP-based model
Xizeng Zhao1, Yong Chen1, Zhenhua Huang2, and Yangyang Gao11Ocean College, Zhejiang University, Zhoushan Zhejiang 316021, China 2Department of Ocean and Resources Engineering, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, USA
Received: 26 Jan 2017 – Accepted for review: 27 Jan 2017 – Discussion started: 02 Feb 2017
Abstract. There is a general lack of the understanding of tsunami wave interacting with complex geographies, especially the process of inundation. Numerical simulations are performed to understand the effects of several factors on tsunami wave impact and run-up in the presence of submarine gentle slopes and coastal cliffs, using an in-house code, named a Constrained Interpolation Profile (CIP)-based model in Zhejiang University (CIP-ZJU). The model employs a high-order finite difference method, the CIP method as the flow solver, utilizes a VOF-type method, the Tangent of hyperbola for interface capturing/Slope weighting (THINC/SW) scheme to capture the free surface, and treats the solid boundary by an immersed boundary method. A series of incident waves are arranged to interact with varying coastal geographies. Numerical results are compared with experimental data and good agreement is obtained. The influences of submarine gentle slope, coastal cliff and incident wave height are discussed. It is found that the rule of tsunami amplification factor varying with incident wave is affected by angle of cliff slope, and there is a critical angle about 45°. The run-up on a toe-erosion cliff is smaller than that on a normal cliff. The run-up is also related to the length of submarine gentle slope with a critical about 2.292 m in the present study. The impact pressure on the cliff is extremely large and concentrated, and the backflow effect is nonnegligible. Results of our work are in high precision and helpful in inversing tsunami source and forecasting disaster.
Zhao, X., Chen, Y., Huang, Z., and Gao, Y.: A numerical study of tsunami wave run-up and impact on coastal cliffs using a CIP-based model, Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2017-37, in review, 2017.