132
CHAPTER 4. HYDRODYNAMIC MODELS
compared with the newly introduced mathematical tidal models.
(Covas 1989).
The present tendency in long-wave modeling is toward Hybrid Models that couple the far-field numerical hydrodynamic model results to a
smaller physical model covering specific problem areas that cannot be handled adequately by the numerical model. This coupling of models can
involve a cross-exchange of results: numerical model results can be used as
external boundary conditions for the physical model, and physical model
measurements can be used as internal boundary conditions in the numerical
simulation. It is possible to automate partially some aspects of the physical
model. Barthel and Funke (1989) provided a thorough discussion of hybrid
model applications.
Bottin (1992) listed several types of problems that can be examined
using long-wave hydrodynamic harbor models:
• Evaluation of proposals to provide for harbor circulation
and/or flushing.
• Studies of flood and ice flow conditions.
• Studies of shoaling conditions at harbor entrances.
• Studies of river flow and sediment movement in rivers that
may enter into harbors or that may impact shorelines adjacent to the harbor.
• Studies of long-period oscillations in the harbor.
• Studies of tidal currents or seiche-generated currents in the
harbor.
It is well known that resonant behavior occurs when a basin (e.g., harbor) is excited by wave motion at periods near its fundamental frequency
modes of oscillation. Hudson, et al. (1979) noted that long-wave physical harbor models can be used to “de-tune” the harbor, and thus decrease
seiching amplitudes. Modifications in a physical model are relatively inexpensive, allowing an optimum design to be achieved so that seiching is kept
to a minimum.
In order to accomplish any of the above tasks, the harbor model must be
constructed accurately to reproduce prototype conditions, and the model
boundary conditions must be well established. If these conditions are
met and economic considerations justify the use of a physical modeling
approach, then a physical harbor model is still the best way to examine
long-wave effects within a harbor or natural basin.
From Eqn. 4.1 we can infer that long waves are defined as
CHAPTER 4. HYDRODYNAMIC MODELS
compared with the newly introduced mathematical tidal models.
(Covas 1989).
The present tendency in long-wave modeling is toward Hybrid Models that couple the far-field numerical hydrodynamic model results to a
smaller physical model covering specific problem areas that cannot be handled adequately by the numerical model. This coupling of models can
involve a cross-exchange of results: numerical model results can be used as
external boundary conditions for the physical model, and physical model
measurements can be used as internal boundary conditions in the numerical
simulation. It is possible to automate partially some aspects of the physical
model. Barthel and Funke (1989) provided a thorough discussion of hybrid
model applications.
Bottin (1992) listed several types of problems that can be examined
using long-wave hydrodynamic harbor models:
• Evaluation of proposals to provide for harbor circulation
and/or flushing.
• Studies of flood and ice flow conditions.
• Studies of shoaling conditions at harbor entrances.
• Studies of river flow and sediment movement in rivers that
may enter into harbors or that may impact shorelines adjacent to the harbor.
• Studies of long-period oscillations in the harbor.
• Studies of tidal currents or seiche-generated currents in the
harbor.
It is well known that resonant behavior occurs when a basin (e.g., harbor) is excited by wave motion at periods near its fundamental frequency
modes of oscillation. Hudson, et al. (1979) noted that long-wave physical harbor models can be used to “de-tune” the harbor, and thus decrease
seiching amplitudes. Modifications in a physical model are relatively inexpensive, allowing an optimum design to be achieved so that seiching is kept
to a minimum.
In order to accomplish any of the above tasks, the harbor model must be
constructed accurately to reproduce prototype conditions, and the model
boundary conditions must be well established. If these conditions are
met and economic considerations justify the use of a physical modeling
approach, then a physical harbor model is still the best way to examine
long-wave effects within a harbor or natural basin.
From Eqn. 4.1 we can infer that long waves are defined as