| Author | Chucheep Wongsupap |
| Call Number | AIT Thesis no.WM-99-02 |
| Subject(s) | Hydraulics
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of
Engineering. |
| Publisher | Asian Institute of Technology |
| Abstract | Analysis of unsteady flow in open channels started more than 180 years ago with
various different methods of analysis. Advanced mathematical treatment of unsteady flow in
open channels started with the development of two partial differential equations and it was
first presented in 1871 by Barre' de Saint-Venant as well known as Saint Venant equations.
These equations consist of two parts that are the continuity part and the momentum part. Due
to inherent mathematical difficulties, these two equations cannot be integrated in closed form
unless many simplifications are introduced.
In the present study, the analytical models for flow routing in open channels under
backwater effects are developed by using the linearized analytical solutions of the one
dimensionless unsteady flow equations, or so called Saint Venant equations. The solutions of
the governing equations were obtained by using mathematical derivation with the
approximation method of Perturbation, dimensionless variables and Laplace transformation
technique. The local inertia term and the convective inertia term are also included in the
derivation. The zeroth order, first order and second order solutions of the governing
equations are derived. Four analytical models namely the diffusion model, the dynamic
model, the local inertial model and the convective inertial model are developed.
The results obtained from this study show that the analytical models could describe
the behavior of wave propagation in open channels taking into account effects of many of
parameters such as type of input, length of the channel, non-linearity and reference
parameters. Results from the analytical model obtained in this study are compared well with
those obtained from the numerical model. It is found that the analytical model with first order
solutions can yield good results for flow under low Froude number and and for flow with
small magnitude of wave at both boundary conditions. And the second order solutions can
improve the accuracy of the analytical model when Froude number and the magnitude of
wave at both boundary conditions becomes larger. |
| Year | 2000 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Tawatchai Tingsanchali; |
| Examination Committee(s) | Izumi, Norihiro;Luketina, David ; |
| Scholarship Donor(s) | Deutsher Akademischer Austauschdienst (DAAD) Partial Scholarship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2000 |