Collecting Data
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3.2.4 Check computer resources
Finally, before you start to set up the model, you should check that you are
not requesting unrealistic computer resources:
The CPU time required should be estimated.
The RAM requirements should be estimated.
The Disk Space required should be estimated.
An estimate of the required CPU and RAM can easily be obtained using the
MIKE 21 BW Model Setup Planner integrated in the Online Help. The disk
space is assessed through the MIKE 21 BW Editor.
Particularly when wave breaking and moving shoreline are included in the
2DH module (space resolution is 1-2 m and temporal resolution 0.02-0.2 s as
typically values) the required CPU time and memory demand can be high (>
12 hours) for large computational domains.
3.3 Collecting Data
This task may take a long time if, for example, you have to initiate a monitor-
ing program. Alternatively it may be carried out very quickly if you are able to
use existing data which are immediately available. In all cases the following
data should be collected:
Bathymetric data such as charts from local surveys or, for example, from
the Hydrographic Office, UK, or MIKE C-MAP
Boundary data, which might be measurements (existing or planned spe-
cifically for your model), observations, wave statistics, etc.
Information on type of structures for assessment of the reflection proper-
ties
Calibration and validation data; these might be measured wave parame-
ters at selected locations, observations, etc.
3.4 Setting up the Model
3.4.1 What does it mean
“Setting up the model” is actually another way of saying transforming real
world events and data into a format which can be understood by the numeri-
cal model MIKE 21 BW. Thus generally speaking, all the data collected have
to be resolved on the spatial grid selected.