Changeset 217 for palm/trunk/DOC/app/chapter_4.3.html

Timestamp:

Dec 9, 2008 6:00:48 PM (16 years ago)

Author:

letzel

Message:

• NCL scripts in trunk/SCRIPTS/NCL updated

File:

• palm/trunk/DOC/app/chapter_4.3.html (modified) (1 diff)

palm/trunk/DOC/app/chapter_4.3.html

@@ -55 +55 @@
 (1) to <b>region</b> (9)), the total domain has the index
 0 (<b>region</b>
-(0)).</p> </td> </tr> </tbody>
+(0)).</p> </td> </tr><tr><td style="vertical-align: top;"><a name="topography_grid_convention"></a><span style="font-weight: bold;">topography_grid_</span><br style="font-weight: bold;"><span style="font-weight: bold;">convention</span></td><td style="vertical-align: top;">C*11</td><td style="vertical-align: top;"><span style="font-style: italic;">default depends on value of <a href="chapter_4.1.html#topography">topography</a>; see text for details</span><span style="font-style: italic;"></span></td><td style="vertical-align: top;">Convention for defining the&nbsp;topography grid.<br><br>Possible values are<br><ul><li><span style="font-style: italic;">'cell_edge':&nbsp;</span>the distance between cell edges defines the extent of topography. This setting is normally for <span style="font-style: italic;">generic topographies</span>, i.e. topographies that are constructed using length parameters. For example, <a href="chapter_4.1.html#topography">topography</a> = <span style="font-style: italic;">'single_building'</span> is constructed using <a href="chapter_4.1.html#building_length_x">building_length_x</a> and <a href="chapter_4.1.html#building_length_y">building_length_y</a>. The advantage of this setting is that the actual size of generic topography is independent of the grid size, provided that the length parameters are an integer multiple of the grid lengths&nbsp;<a href="chapter_4.1.html#dx">dx</a> and&nbsp;<a href="chapter_4.1.html#dy">dy</a>. This is convenient&nbsp;for resolution parameter studies.</li><li><span style="font-style: italic;">'cell_center'</span><span style="font-style: italic;">:&nbsp;</span>the number of topography cells define the extent of topography. This setting is normally for <span style="font-style: italic;">rastered real topographies</span> derived from digital elevation models.&nbsp;For example, <a href="chapter_4.1.html#topography">topography</a> = <span style="font-style: italic;">'read_from_file'</span> is constructed using&nbsp;the input file <a href="chapter_3.4.html#TOPOGRAPHY_DATA">TOPOGRAPHY_DATA</a><font color="#000000">.&nbsp;</font>The
+advantage of this setting is that the&nbsp;rastered topography cells of
+the input file are directly mapped to topography grid boxes in PALM. <span style="font-style: italic;"></span></li></ul>The example files for&nbsp;<big><code>sgl_bldg_cell_center</code></big> and
+<big><code>sgl_bldg_cell_edge</code></big> in <big><code>trunk/EXAMPLES/</code></big>
+illustrate the difference between
+both approaches. Both examples simulate a single building and yield the
+same results. The former uses a rastered topography input file with <span style="font-style: italic;">'cell_center'</span> convention, the latter applies a generic topography with <span style="font-style: italic;">'cell_edge'</span> convention.<br><br>The default value is<br><ul><li><span style="font-style: italic;">'cell_edge' </span>if <a href="chapter_4.1.html#topography">topography</a> = <span style="font-style: italic;">'single_building'</span>,</li><li><span style="font-style: italic;">'cell_center'</span><span style="font-style: italic;"></span> if <a href="chapter_4.1.html#topography">topography</a> = <span style="font-style: italic;">'read_from_file'</span>,</li><li><span style="font-style: italic;">none (' '</span> ) otherwise, leading to an abort if&nbsp;<span style="font-weight: bold;">topography_grid_convention</span> is not set.</li></ul>This means that <br><ul><li>For PALM simulations using a <span style="font-style: italic;">user-defined topography</span>, the<span style="font-weight: bold;"> topography_grid_convention</span> must be explicitly set to either <span style="font-style: italic;">'cell_edge'</span> or <span style="font-style: italic;">'cell_center'</span>.</li><li>For PALM simulations using a <span style="font-style: italic;">standard topography</span> <span style="font-style: italic;">('single_building'</span> or <span style="font-style: italic;">'read_from_file')</span>, it is possible but not required to set the&nbsp; <span style="font-weight: bold;">topography_grid_convention</span> because appropriate default values apply</li></ul></td></tr> </tbody>
 </table><p style="line-height: 200%;">&nbsp; <br>
 &nbsp; </p>