1 MIKE Flood An integrated tool for flood plain and storm surge studies MIKE Flood combines lMIKE 11 lMIKE 21

2 MIKE Flood MIKE Flood is used If a two-dimensional (MIKE21) description is needed in some areas and where significant benefits exist when combined to a one-dimensional (MIKE11) model

3 MIKE Flood Examples : A detailed velocity pattern is required locally (MIKE21) but exchange of flows with the river is regulated by complex structures (movable gates, culverts, special weirs etc.) simulated in a MIKE11 model A general MIKE11 model for multiple purpose (eg. flow analysis, water quality, sediment transport, flood forecasting) can provide boundary condition to a local two- dimensional area (and vice-versa)

4 Coupling of MIKE 11 and MIKE 21 Øadvection-dispersion Øhydrodynamics MIKE FLOOD Bay of Bengal, Bangladesh 2-D Model of two- dimensional flow 1-D Model of one- dimensional flow

5 MIKE 11 boundary to a MIKE 21 boundary Types of coupling Lake, estuary etc. MIKE 11 boundary to a MIKE 21 source point Flood plain

6 ØDifferent Time step in MIKE11 and MIKE21 Time Integration Mike 21Mike 11 n n+1 ØData exchange at mike11 time step n and n+1 ØMIKE11 always ahead: MIKE21 value at time step n applied as boundary condition at time step n+1 to progress MIKE11 with the next time step. Following the MIKE11 time step, the MIKE21 executes (smaller) time steps up to new n+1.