Abstract:
The coastal area of Bangladesh is different from the rest of the country due to its unique
geo-physical characteristics and vulnerability due to several natural disasters like erosion,
cyclone, storm surges, tsunami, sea level rise, settlement and also various forms of
pollution. These natural hazards are increasing with high frequency and intensity along the
coast of Bangladesh and adversely affected lives and livelihoods in the coastal zone and
slowed down the pace of social and economic developments in this region. Water
movement in the coastal zone of Bangladesh is determined by the wave coming from the
Bay of Bengal and other meteorological conditions.
A mathematical model study has been carried out to simulate the maximum wave height in
the nearshore coastline of the Cox's Bazar area in Bangladesh. In this study a two
dimensional hydrodynamic model DIVAST (Depth Integrated Velocity and Solute
Transport) has been established based on different parameters like co-efficient of eddy
viscosity, Manning roughness coefficient, advective and diffusion co-efficient etc. The
DIVAST model is based on FORTRAN PROGRAMING and it has a number of modules
for different purposes with different sets of equations.
The hydrodynamics of the selected area of the Bay of Bengal has been simulated by
solving two-dimensional depth integrated momentum and continuity equations numerically
with finite difference method. Consequently the respective velocity components in the x
and y directions has been calculated across the selected coastal domain for real set of initial
and boundary conditions. The hydrodynamic model has been set up at neareshore coastal
water of Cox’s Bazar in Bay of Bengal. The model output consists of wave height, wave
direction, celerity, group velocity and water velocity at different grid point in the study
area of Bay of Bengal. In this study, velocity profile has been observed and simulated for
different wave angle from offshore area and also the neareshore wave climate has been
developed. Simulated maximum wave height is verified at selected locations of coastal
area with the measured field data, that is the maximum wave height along the coastal zone
of Cox’s Bazar coastline in Bangladesh. The output from the mathematical model
DIVAST shown very good agreement with the measured data. These simulated results can
be used for nearshore wave climate around the area. As a conclusion it can be said that the
DIVAST model simulate reasonably sound output data for the selected domain of the
nearshore zone of the Cox’s Bazar area in Bangladesh.
