Changes between Version 10 and Version 11 of doc/tec/topography

Timestamp:

Jun 6, 2017 2:16:50 PM (8 years ago)

Author:

suehring

Comment:

--

doc/tec/topography

@@ -246 +246 @@
 ''surf_X_h(1)'' encompass all horizontally downward-facing surfaces of its respective type, \\
 ''surf_X_h(0)'' encompass the model top grid points. \\
-
 Please note, downward-facing (and model top) surfaces belong always to the default type at the moment.  
 
+Furthermore,\\
 ''surf_X_v(0)'' encompass all vertically northward-facing surfaces of its respective type, \\
 ''surf_X_v(1)'' encompass all vertically southward-facing surfaces of its respective type, \\
@@ -257 +257 @@
 In the future, however, different surface types can co-exist next to each other, i.e. it is possible to define areas where the urban-surface model and areas where the land-surface model is executed at the same time. 
 
+
+'''Outline of technical realization'''
+
+At first, the number of surface elements of its respective type and orientation is counted and stored within the data-structure:
+
+{{{
+#!Latex
+\begin{verbatim}
+surf_def_h(0)%ns = 120  !< number of horizontal upward-facing surface elements on local processor
+surf_def_h(1)%ns = 12   !< number of horizontal downward-facing surface elements on local processor
+
+surf_def_v(0)%ns = 50   !< number of vertical northward-facing surfaces on local processor
+surf_def_v(1)%ns = 31   !< number of vertical southward-facing surfaces on local processor
+surf_def_v(2)%ns = 19   !< number of vertical eastward-facing surfaces on local processor
+surf_def_v(3)%ns = 39   !< number of vertical westward-facing surfaces on local processor
+\end{verbatim}
+}}}
+
+In the following, surface attributes are allocated for the exact number of surface elements of the respective type:
+{{{
+#!Latex
+\begin{verbatim}
+ALLOCATE ( surf_def_h(0)%i(1:surf_def_h(0)%ns) )   !< allocate i index
+ALLOCATE ( surf_def_h(0)%j(1:surf_def_h(0)%ns) )   !< allocate j index
+ALLOCATE ( surf_def_h(0)%k(1:surf_def_h(0)%ns) )   !< allocate k index
+ALLOCATE ( surf_def_h(0)%shf(1:surf_def_h(0)%ns) ) !< allocate heat flux
+\end{verbatim}
+}}}
+
+Here, ''i, j, k'' are the corresponding indices linking the surface element to the 3D grid, and ''shf'' is the surface heat flux. 
+Please note, there are many other attributes allocated.  
+
+A certain variable within the data-structure can be accessed: 
+{{{
+#!Latex
+\begin{verbatim}
+DO  m = 1, surf_def_h(0)%ns
+   surf_def_h(0)%shf(m) = ...
+ENDDO
+\end{verbatim}
+}}}
+
+Finally, the resulting fluxes are added to the prognostic terms in following way:
+
+{{{
+#!Latex
+\begin{verbatim}
+DO m = 1, surf_def_h(0)%ns
+   i  = surf_def_h(0)%i(m)
+   j  = surf_def_h(0)%j(m)
+   k = surf_def_h(0)%k(m)
+   tend(k,j,i) = tend(k,j,i) + surf_def_h(0)%shf(m) * ddz(k)
+ENDDO
+\end{verbatim}
+}}}
+Summarized, the surface data-structure {{{surf_type}}} is used to store and access all surface related quantities in an optimized memory demand. Several adjoining surfaces at a grid cell (e.g. at corners) are treated separately. The new data-structure is also applied in the flat case without any topography.  
+
+'''Some notes''': So far, downward-facing walls are only realized for default surface type. 
+