MIKE 21 BW - General Description; 2 Introduction

General Description
9
2 Introduction
2.1 General Description
The two modules included in the MIKE 21 BW are based on the numerical
solution of time domain formulations of Boussinesq type equations. The
Boussinesq equations include nonlinearity as well as frequency dispersion.
Basically, the frequency dispersion is introduced in the momentum equations
by taking into account the effect of vertical accelerations on the pressure dis-
tribution. Both modules solve the Boussinesq type equations using a flux-for-
mulation with improved linear dispersion characteristics. These enhanced
Boussinesq type equations (originally derived by Madsen et al, 1991, and
Madsen and Sørensen, 1992)
(1)
make the modules suitable for simulation of
the propagation of directional wave trains travelling from deep to shallow
water. The maximum depth to deep-water wave length is h/L
0
 0.5. For the
classical Boussinesq equations the maximum depth to deep-water wave
length is h/L
0
 0.22.
The model has been extended into the surf zone by inclusion of wave break-
ing and moving shoreline as described in Madsen et al (1997a,b)
(1)
,
Sørensen and Sørensen (2001)
(1)
and Sørensen et al (1998, 2004).
Figure 2.1 MIKE 21 BW is a state-of-the-art numerical tool for studies and ana-
lysis of short and long period waves in ports and harbours and coastal
areas
1 The papers are included in the Scientific Documentation