3 research outputs found

    Validation Of Integrated Coast-Ocean Model Cche2D-Coast And Development Of Wind Model

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    The eastern and southern coastlines of the United States are two of the most cyclone-prone areas of the world. The effects of tropical cyclones vary mainly depending on wind intensity and geological features of the coast that it is crossing. Higher winds potentially generate higher storm surges and consequently larger floods occur along the coastlines. Therefore, it is critical to accurately predict winds, storm surge, and waves associated with a hurricane. In the present study, an integrated coastal and ocean process model, CCHE2D-Coast, is validated by assessing the model’s capabilities in simulating coast-ocean circulations driven by the astronomical tides on the U.S. East Coast. Through the skill assessment, discrepancies between numerically simulated water surface elevations and observed tidal elevations at NOAA tide gages are quantified. On the other hand, statistical errors of the tidal constituents parameters, amplitude and phase, are also determined. In this study, the tidal harmonic constants are identified by using a newly-developed parameter identification approach. CCHE2D-Coast is also further examined under meteorological forces driven by a hurricane. CCHE2D-Coast is applied to simulate meteorological and hydrodynamic processes during Hurricane Bob (1991) on the US Atlantic coast. Hindcasting storm surges and waves induced by Bob’s winds and tides were performed before and after the landfall of this hurricane. The results shothat the model performed well in reproducing the dynamic process driven by astronomical and meteorological forces. To improve the model’s accuracy in reproducing hurricane wind fields during a real-time hurricane forecast, a hurricane wind model is developed in order to incorporate asymmetric effects into the Holland parametric wind model. The method is validated using the National Oceanic and Atmospheric Administration (NOAA)/ National Hurricane Center (NHC)/ Automated Tropical Cyclone Forecast’s (ATCF) guidelines. The best track date, which contains six-hourly information on the location, maximum winds, radii of 3 wind isotach, and central pressure of Hurricane Gustave (2008) is used to compute the wind field in the Gulf of Mexico. The simulation result suggests that the wind model performed well in reconstructing wind field. The asymmetric model captured the directional change of hurricane wind velocity around the storm center

    A SIMPLIFIED PROCEDURE TO ASSESS THE DYNAMIC PRESSURES ON LOCK GATES

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    peer reviewedThe paper is concerned with the seismic design of lock gates. During an earthquake, it is evident that the liquid contained in the lock chamber is responsible for an additional hydrodynamic pressure acting on the structure. This one is known to have three different contributions, which are respectively called the convective, rigid and flexible impulsive parts. The two first ones have already been extensively studied in the literature and are quite easy to evaluate. Nevertheless, characterizing the flexible contribution is more difficult, as it is largely influenced by the coupling occurring between the fluid and the gate. The only relevant way to overcome this difficulty seems to resort to finite elements software, which is not always convenient. Therefore, some research have been undertaken to provide a rapid meshless method leading to an approximation of the flexible pressure on lock gates. As detailed in the present paper, this is achieved by applying an analytical approach based on the virtual work principle. As a matter of validation, the results obtained analytically are compared to numerical solutions. The agreement between both of them is found to be satisfactory
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