<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html
  SYSTEM "about:legacy-compat">
<html xmlns:mml = "http://www.w3.org/1998/Math/MathML" lang = "en"><head><meta charset = "UTF-8"/><meta name = "copyright" content = "(C) Copyright 2020"/><meta name = "DC.rights.owner" content = "(C) Copyright 2020"/><meta name = "DC.type" content = "concept"/><meta name = "abstract" content = "Use the transition zone manufacturing constraint to gain a smoother transition from design area to nondesign area."/><meta name = "description" content = "Use the transition zone manufacturing constraint to gain a smoother transition from design area to nondesign area."/><meta name = "DC.relation" scheme = "URI" content = "../TsoCmdMap/tso-r-cmd-dvconShape.htm#tso-r-cmd-dvconShape"/><meta name = "DC.relation" scheme = "URI" content = "tso-c-usr-shape-desArea-smooth.htm"/><meta name = "DC.format" content = "HTML5"/><meta name = "DC.identifier" content = "tso-c-usr-shape-desArea-dvcTransition"/><meta name = "DC.language" content = "en"/><link rel = "stylesheet" type = "text/css" href = "../DSDocUI_XML34.css"/><title>Transition Zone</title>
<script type = "text/javascript" src = "../DSDocUI_Highlight34.js">
  	/* */
  	</script></head><body onLoad = "highlightSearchTerms();" id = "tso-c-usr-shape-desArea-dvcTransition">
<a name = "hj-top"> </a><table class = "table1" id = "table11"><tr><td><table class = "DocHeader"><tr><td class = "DocHeader1" colspan = "2"><h1>Transition Zone</h1></td></tr><tr><td class = "DocHeader4" colspan = "2"/></tr><tr><td class = "DocHeader3"><table class = "DocHeaderIntro" id = "table12"><tr><td class = "Intro1Only"><p class = "header"><p class = "abstract">
<span class = "shortdesc"> Use the transition zone manufacturing constraint to gain a smoother transition from design area to nondesign area.</span>

</p>

</p></td></tr></table></td><td class = "DocHeader2"><table class = "DocTopicsSeeAlso" id = "table13"><tr><td class = "TopicsTitle">See Also</td></tr><tr><td><a title = "In shape optimization, the surface of a component is modified. If only the surface nodes are displaced and the inner nodes remain at their location, the surface layer elements will be strongly distorted. As a result, the quality of the FE calculation suffers and might no longer form a reliable basis for the optimization. To ensure realistic and high-quality results, a displacement of the surface usually necessitates a mesh displacement (mesh smoothing) in the inner of the structure in most cases." href = "tso-c-usr-shape-desArea-smooth.htm">About Mesh Smoothing (MESH_SMOOTH)</a></td></tr></table><table class = "DocTopicsInOtherGuides" id = "table14"><tr><td height = "8px"/></tr><tr><td class = "TopicsTitleNormal">In Other Guides</td></tr><tr><td><a title = "Defines restrictions of the design variables in shape optimization." href = "../TsoCmdMap/tso-r-cmd-dvconShape.htm#tso-r-cmd-dvconShape">DVCON_SHAPE</a></td></tr></table></td></tr></table>




<div class = "body conbody">
<p>
<table class = "table"><caption/><colgroup><col style = "width:33.33333333333333%"/><col style = "width:33.33333333333333%"/><col style = "width:33.33333333333333%"/></colgroup><thead class = "thead">
<tr class = "row">
<th class = "entry" id = "tso-c-usr-shape-desArea-dvcTransition__entry__1">Applicable for</th>
<th class = "entry align-center" id = "tso-c-usr-shape-desArea-dvcTransition__entry__2">Controller (SHAPE_CONTROLLER)</th>
<th class = "entry align-center" id = "tso-c-usr-shape-desArea-dvcTransition__entry__3">Sensitivity (SHAPE_SENSITIVITY)</th>
</tr>
</thead><tbody class = "tbody">
<tr class = "row">
<td class = "entry" headers = "tso-c-usr-shape-desArea-dvcTransition__entry__1">TRANSITION</td>
<td class = "entry align-center" headers = "tso-c-usr-shape-desArea-dvcTransition__entry__2">OK</td>
<td class = "entry align-center" headers = "tso-c-usr-shape-desArea-dvcTransition__entry__3">OK</td>
</tr>
</tbody></table>
</p>

<p>
A transition area shall create a smooth transition from design nodes to nondesign nodes.
<span class = "ph">Tosca</span>
supports defining a transition area by using mesh smooth options. But these transition
areas are located outside of the design area. This manufacturing constraint is used to create
the transition area as part of the design area.
</p>
<p>
The command is explained with the following example code block.
<pre class = "codeblock">
DVCON_SHAPE
  ID_NAME         = MY_TRANSITION_AREA
  ND_GROUP        = &lt;node_group_name&gt;
  REFERENCE_NDGR  = &lt;node_group_fixed_edge&gt;
  CHECK_TYPE      = TRANSITION
  [CHECK_NDGR     = &lt;design area nodes without &lt;node_group_name&gt; &gt;]
  FUNCTION        = <span class = "ph uicontrol">SMOOTH</span> | LINEAR
END_
</pre>

<ul class = "ul">
<li class = "li"><code class = "ph codeph">ND_GROUP</code>: Nodes that form the transition area.</li>
<li class = "li"><code class = "ph codeph">REFERENCE_NDGR</code>: The nodes on the fixed edge.</li>
<li class = "li"><code class = "ph codeph">CHECK_NDGR</code>: The distance of <code class = "ph codeph">ND_GROUP</code> to the design area must be determined. But in some cases the model might be in such a way,
                                 that the distance of some nodes to the design area is not as desired: In the figure below, most of the transition nodes will get the distance
                                 to the lower part of the design area. In such cases, only the upper part of the design area can be specified with <code class = "ph codeph">CHECK_NDGR</code>.</li>
<li class = "li"><code class = "ph codeph">FUNCTION</code>: Control the form of the transition area.</li>
</ul>
<br/><img class = "image" src = "../TsoUserImages/tso-c-usr-shape-desArea-dvcTransition_checkndgr.png"/><br/></p>

<p>The functionality is similar to the <code class = "ph codeph">MESH_SMOOTH -&gt; FREE_SF</code> command. Both aim for building transitions between design- and nondesign area.</p>
<p>A transition zone was traditionally defined outside the design area and implicitly with the number of element layers in <code class = "ph codeph">MESH_SMOOTH</code>.
<br/><img class = "image" src = "../TsoUserImages/tso-c-usr-shape-desArea-dvcTransition_freesf.png"/><br/></p>
<p>With the definition of the transition zone as <code class = "ph codeph">DVCON</code> command, an explicit definition inside the design area is possible. This gives more flexibility and control.
<br/><img class = "image" src = "../TsoUserImages/tso-c-usr-shape-desArea-dvcTransition_transition.png"/><br/></p>
<p><table class = "Remark" id = "table132"><tr><td class = "Remark"><span class = "run-in.tip">Tip:
				</span><span class = "notecontent">
The group used in the <code class = "ph codeph">REFERENCE_NDGR</code> item is thought to lie outside the design area and be already fixed.
However, this is not mandatory and <span class = "ph">Tosca</span> does not take any automatic action to fix this group.
To be on the safe side, it is good practice to fix the node group using a <code class = "ph codeph">CHECK_DOF = CS_0, FIX, FIX, FIX</code> in a <code class = "ph codeph">DVCON_SHAPE</code> command.
</span></td></tr></table>
</p>
</div>

<div class = "related-links"/>
</td></tr></table><script type = "text/javascript" src = "../DSDocUI_Bottom34.js">/* */</script></body>
</html>
