1.   Purpose and objectives

     To provide a computational method for the vertically integrated salinity distribution in an estuary. The model computes the two dimensional horizontal velocity distribution and the variation of the tidal water level. Some pollutant dispersion problems in  rivers and estuaries can also be computed by using the scheme of this method.

2.   Description

     The model includes two parts, that is a hydrodynamical model for solving the velocity field and a salt transport model for solving the salinity field.

     The model uses the finite element method, which can easily handle the complicated topography of the river bed and bank. The explicit solution scheme by using a lumping technique may save computer storage and running time.

     The Coriolis parameter, the roughness and dispersion coefficients in the governing equations are taken into account, and an empirical relationship between nondimensional dispersion coefficient and
nondimensional characteristic velocity is used to estimate the value of the dispersion coefficient.

3.   Input

     Boundary data including the variation of tidal water level or tidal velocity and salinity with time, and data on river bed topography, and physical parameters are needed.

4.   Output

     Calculated results, including tidal water level, velocity components (longitudinal and transverse) and salinity distribution.

5.   Operational requirements and restrictions

     The chosen computer need to satisfy the requirements of storage and running speed, which are determined by the area of calculation and number of grid nodal.

6.   Form of presentation

     Program in FORTRAN and user manuals.

7.   Operational experience

     The model has been used in the Yangtze Estuary in China since 1982 and the calculated results agree well with the natural data. The same method was also used to study pollutant dispersion in this estuary in 1985 and the comparisons between calculated results and measuring results in the physical model and field prove that the method is successful.

8.   Originator and technical support

     Nanjing Hydraulic Research Institute, Nanjing, China.

9.   Availability

     From the HOMS National Reference Centre for China.

10.  Conditions on use

     Cost of reproduction and mailing.