| Author | Pun, Kwock Leung |
| Call Number | AIT Thesis no. WA-91-16 |
| Subject(s) | Hydrodynamics--Mathematical models
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of
Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | A finite difference numerical model is developed to predict the hydrodynamic circulation in
bays. Applying the multi-level approach, the water body is divided into three levels, in which the
interfacial layers are fixed in space. The links between layers are the vertical mass exchange and
momentum transfer in terms of interfacial shear stress. The thickness of upper and middle layers
are decided according to the field measured data taken from Tokyo Bay on May 23, 1983 to represent
an approximate thickness of a thermocline. The formulation of hydrodynamic model is based on
the vertical integration of continuity and momentum equation for each layer. To study the dispersion
of substances in bays, a multi-level approach is also used to formulate a three-level dispersion model.
Mass transport and diffusive flux between layers are included in the model. The formulation of
dispersion model is based on the vertical integration of convection-diffusion equation between the
layer boundaries. An important connection between two models is that the computed layer velocities
and water elevation from the hydrodynamic model serve as input data to the dispersion model.
Consequently, the validity of the three-level hydrodynamic model is examined by comparing
the computed flow condition with the field data measured at 9 sampling points in Tokyo Bay. The
computed results seem in reasonable agreement with the measured data. Moreover, the important
factors which affect the flow condition as well as the dispersion process - such as wind condition,
interfacial shear stress coefficient, residual cunent, initial and boundary conditions - are discussed.
The river discharge does not have much effect on the entire flow pattern except in the vicinity of
the river mouth. Under the wind effect, flow direction is usually deflected in the upper layer and
has a tendency to align with the wind direction. In the middle and lower layer, a return flow is driven
to a direction opposite to the upper layer flow for compensation. |
| Year | 1991 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Water Resources Research Engineering (WA) |
| Chairperson(s) | Shibayama, Tomoya
|
| Examination Committee(s) | Suphat Vongvisessomjai ;Tawatchai Tingsanchali |
| Scholarship Donor(s) | The Royal Thai Government |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1991 |