On the basis of the transient water wave (TWW) theory, focused wave is generated in the circulating
water channel. Numerical simulation of the focused wave is carried out by solving the Reynolds averaged Navier-
Stokes (RANS) equations. The dynamic grid technique is adopted to simulate the motion of the wave maker, and
the volume of fluid (VOF) method is used to capture the free surface of the wave. The simulation results are
compared with the measured data, and good agreement is obtained. For quantitative estimation of the numerical
simulation error and uncertainty, the uncertainty analysis method recommended by the International Towing
Tank Conference (ITTC) procedure is performed for the simulation results of the surface elevations at different
positions. Both grid-convergence and time-step-size convergence studies are conducted using three types of grids
and time step sizes. The simulation results are all monotonously convergent in the verification procedure, and
the validations of the simulated surface elevations with the positions at 3.5, 4.0 and 4.5m are all achieved by
comparing with the validation uncertainty. It is found that the numerical simulation errors caused by the grid
and time-step-size in the convergence studies have the same order of magnitude. In addition, the numerical errors
and uncertainties for the surface elevations at different positions are compared and discussed in detail. This
paper presents the first attempt to carry out the uncertainty analysis of the simulation of focused wave, and the
effectiveness of the proposed verification and validation procedures in the uncertainty analysis is demonstrated.
BAI Junli (柏君励), MA Ning (马宁), GU Xiechong (顾解忡)
. Numerical Simulation of Focused Wave and Its Uncertainty Analysis[J]. Journal of Shanghai Jiaotong University(Science), 2018
, 23(4)
: 475
.
DOI: 10.1007/s12204-018-1970-5
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