Hi Ikka,
The major difference is FM (Flexible mesh) solves the equations in
Selection of preferred modelling software based on:
[list]
[li]Model calibration - FM gives a slightly better calibration as it resolves all features
Run times - Rectilinear usually uses a single core may take more time than FM which are capable of using all the processing capacity
Representation of complex features - rectilinear may miss some complex feature especially when the model is having estuaries/channels
Wetting and drying of intertidal mudflats - better resolved in FM
Resolution - unlike FM, Rectilinear are fixed cell size. In order to increase or reduce the resolution you need to create nested bathymetry and which got risk of improper boundary transfers, which can be avoided in FM [/li]
[li][/li]
[/list]
Hope this helps
Regards,
Murali
