Start Date

2018 12:15 PM

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.

Abstract

To assess the longitudinal force on a ship in a lock chamber in a design phase, mostly numerical modelling is carried out. This paper compares the longitudinal forces on a ship in the lock chamber computed with the software programs VUL_SLUIS, LOCKFILL, LOCKSIM and DELFT3D. Therefore, 16 cases of levelling a lock chamber are selected, differing in lock type, ship type, type of levelling operation, the type of openings in the lock gate and the valve type. These cases are simulated with the four considered software programs. The variation in time of the computed discharge through the openings in the lock gate, the computed water level in the lock chamber and levelling times are only briefly discussed, while the computed longitudinal forces are discussed into detail. When the lock is emptied or when the filling of the lock is dominated by translatory waves, the four different software programs compute comparable forces on the ship in the lock chamber. For filling a lock when multiple force components are relevant, LOCKFILL and VUL_SLUIS compute comparable longitudinal forces on the ship, these forces being higher than those computed with LOCKSIM and DELFT3D. The latter two programs compute comparable forces. The frequency analysis of the predicted time series of longitudinal forces on the ship in the lock chamber shows that the spectrum corresponding to VUL_SLUIS, LOCKFILL and LOCKSIM is characterized by the presence of the same peak frequency components. The damping and to a lesser extent the frequency of the forces computed with DELFT3D, however, depend on the discharge through the openings in the lock gate that is used as input.

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May 17th, 12:15 PM

Comparison of Software for Computation of Longitudinal Forces on a Ship in a Lock Chamber During Levelling with Openings in the Lock Gate

To assess the longitudinal force on a ship in a lock chamber in a design phase, mostly numerical modelling is carried out. This paper compares the longitudinal forces on a ship in the lock chamber computed with the software programs VUL_SLUIS, LOCKFILL, LOCKSIM and DELFT3D. Therefore, 16 cases of levelling a lock chamber are selected, differing in lock type, ship type, type of levelling operation, the type of openings in the lock gate and the valve type. These cases are simulated with the four considered software programs. The variation in time of the computed discharge through the openings in the lock gate, the computed water level in the lock chamber and levelling times are only briefly discussed, while the computed longitudinal forces are discussed into detail. When the lock is emptied or when the filling of the lock is dominated by translatory waves, the four different software programs compute comparable forces on the ship in the lock chamber. For filling a lock when multiple force components are relevant, LOCKFILL and VUL_SLUIS compute comparable longitudinal forces on the ship, these forces being higher than those computed with LOCKSIM and DELFT3D. The latter two programs compute comparable forces. The frequency analysis of the predicted time series of longitudinal forces on the ship in the lock chamber shows that the spectrum corresponding to VUL_SLUIS, LOCKFILL and LOCKSIM is characterized by the presence of the same peak frequency components. The damping and to a lesser extent the frequency of the forces computed with DELFT3D, however, depend on the discharge through the openings in the lock gate that is used as input.