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      <title>TABDMP1</title>
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      <div class="title_refTopic" id="xps10_pagetitle">TABDMP1 </div>
      <hr noshade="true">
      <h4 class="refClassification">Modal Damping Table </h4>
      <p class="para_refTopic">Defines modal damping as a tabular function of natural frequency. </p>
      <div class="title_refCategory">Format: </div>
      <div class="refCategoryContent">
         <table border="1" width="100%" align="center">
            <colgroup span="1">
               <col span="1" width="11.36*">
               <col span="1" width="11.36*">
               <col span="1" width="11.36*">
               <col span="1" width="9.47*">
               <col span="1" width="9.66*">
               <col span="1" width="9.85*">
               <col span="1" width="9.85*">
               <col span="1" width="9.66*">
               <col span="1" width="9.09*">
               <col span="1" width="8.34*">
            </colgroup>
            <thead>
               <tr>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">1 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">2 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">3 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">4 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">5 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">6 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">7 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">8 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">9 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">10 </p>
                  </th>
               </tr>
            </thead>
            <tbody>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">TABDMP1 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">TID </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">TYPE </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
               </tr>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">f1 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">g1 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">f2 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">g2 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">f3 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">g3 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">-etc.- </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
               </tr>
            </tbody>
         </table><br></div>
      <div class="title_refCategory">Example: </div>
      <div class="refCategoryContent">
         <table border="1" width="100%" align="center">
            <colgroup span="1">
               <col span="1" width="11.33*">
               <col span="1" width="10.77*">
               <col span="1" width="10.77*">
               <col span="1" width="10.77*">
               <col span="1" width="10.77*">
               <col span="1" width="10.77*">
               <col span="1" width="8.44*">
               <col span="1" width="8.26*">
               <col span="1" width="9.16*">
               <col span="1" width="8.98*">
            </colgroup>
            <tbody>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">TABDMP1 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">2 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
               </tr>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">2.5 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">.01057 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">2.6 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">.01362 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">ENDT </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
               </tr>
            </tbody>
         </table><br></div>
      <div class="title_refCategory">Fields:</div>
      <div class="refCategoryContent">
         <table cellpadding="9" width="100%" align="center">
            <colgroup span="1">
               <col span="1" width="17.55*">
               <col span="1" width="82.45*">
            </colgroup>
            <thead>
               <tr>
                  <th align="left" colspan="1" rowspan="1">
                     <p class="para_th"><b class="uiTerm">Field </b></p>
                  </th>
                  <th align="left" colspan="1" rowspan="1">
                     <p class="para_th"><b class="uiTerm">Contents </b></p>
                  </th>
               </tr>
            </thead>
            <tbody>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">TID </p>
                  </td>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">Table identification number.  (Integer &gt; 0) </p>
                  </td>
               </tr>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">TYPE </p>
                  </td>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">Type of damping units.  (Character: &ldquo;G&rdquo;, &ldquo;CRIT&rdquo;, or &ldquo;Q&rdquo;; Default is &ldquo;G&rdquo;) </p>
                  </td>
               </tr>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">fi </p>
                  </td>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">Natural frequency value in cycles per unit time.  (Real &ge; 0.0) </p>
                  </td>
               </tr>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">gi </p>
                  </td>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">Damping value.  (Real) </p>
                  </td>
               </tr>
            </tbody>
         </table><br></div>
      <div class="title_refCategory">Remarks: </div>
      <div class="refCategoryContent">
         <ol type="1" start="1">
            <li>
               <p class="para_item">Modal damping tables must be selected with the Case Control command SDAMPING=TID. </p>
            </li>
            <li>
               <p class="para_item">The frequency values, fi, must be specified in either ascending or descending order, but not both. </p>
            </li>
            <li>
               <p class="para_item">Discontinuities may be specified between any two points except the two starting points or two end points.  For example, in <a class="links" href="javascript:void(0)" onclick="top.openFile('QRG/20topic_2.html#ref37496');return(false);">Figure 19-</a> discontinuities are allowed only between points f2 through f7.  Also, if g is evaluated at a discontinuity, then the average value of g is used.  In <a class="links" href="javascript:void(0)" onclick="top.openFile('QRG/20topic_2.html#ref37496');return(false);">Figure 19-</a>, the value of g at f=f3 is <em>g</em>=(<em>g</em>3+<em>g</em>4) / 2. 
               </p>
            </li>
            <li>
               <p class="para_item">At least one continuation entry must be specified. </p>
            </li>
            <li>
               <p class="para_item">Any fi or gi entry may be ignored by placing &ldquo;SKIP&rdquo; in either of the two fields used for that entry. </p>
            </li>
            <li>
               <p class="para_item">The end of the table is indicated by the existence of &ldquo;ENDT&rdquo; in either of the two fields following the last entry.  An error is detected if any continuations follow the entry containing the end-of-table flag &ldquo;ENDT&rdquo;. </p>
            </li>
            <li>
               <p class="para_item">The TABDMP1 uses the algorithm </p>
               <p align="center"><img align="bottom" src="graphics/bulktuv-equ01.gif"></p>
               <p class="para_item">where <em>f</em> is input to the table and <em>g</em> is returned.  The table look-up <em>g<sub class="subscript">T</sub></em>(<em>f</em>) is performed using linear interpolation within the table and linear extrapolation outside the table using the last two end points.  See <a class="links" href="javascript:void(0)" onclick="top.openFile('QRG/20topic_2.html#ref37496');return(false);">Figure 19-</a>.  No warning messages are issued if table data is input incorrectly. 
               </p><a name="ref37496"></a><div class="figure">
                  <p align="center"><img align="bottom" src="graphics/bulktuv-fig01.gif"></p>
               </div>
               <div class="title_figure">Figure. Example of Table Extrapolation and Discontinuity </div>
            </li>
            <li>
               <p class="para_item">This form of damping is used only in modal formulations of complex eigenvalue analysis, frequency response analysis, or transient response analysis.  The type of damping used depends on the solution sequence (structural damping is displacement-dependent, and viscous damping is velocity-dependent).  See <a class="links" href="javascript:void(0)" onclick="top.popUpPage('User/index.html?goto=User/14ref37867_31.html&vars=-aux,-home','linkInter','menubar=yes,status=yes,resizable=yes,toolbar=yes,scrollbars=yes,location=no,directories=no');return(false);">&ldquo;Formulation of Dynamic Equations in SubDMAP GMA&rdquo; </a>in the <em>NX Nastran User&rsquo;s Guide</em> for the equations used. 
               </p>
            </li>
            <li>
               <p class="para_item">PARAM,KDAMP may be used in solution sequences that perform modal frequency and modal complex analysis, to select the type of damping. </p>
               <table border="1" width="100%" align="center">
                  <colgroup span="1">
                     <col span="1" width="51.19*">
                     <col span="1" width="48.81*">
                  </colgroup>
                  <thead>
                     <tr>
                        <th align="center" colspan="1" rowspan="1">
                           <p class="para_th"><b class="uiTerm">KDAMP </b></p>
                        </th>
                        <th align="center" colspan="1" rowspan="1">
                           <p class="para_th"><b class="uiTerm">Result </b></p>
                        </th>
                     </tr>
                  </thead>
                  <tbody>
                     <tr>
                        <td align="left" colspan="1" rowspan="1" valign="top">
                           <p class="para_td">1 (Default) </p>
                        </td>
                        <td align="left" colspan="1" rowspan="1" valign="top">
                           <p class="para_td"><em>B</em> Matrix 
                           </p>
                        </td>
                     </tr>
                     <tr>
                        <td align="left" colspan="1" rowspan="1" valign="top">
                           <p class="para_td">-1 </p>
                        </td>
                        <td align="left" colspan="1" rowspan="1" valign="top">
                           <p class="para_td">(1+<em>ig</em>) <em>K</em></p>
                        </td>
                     </tr>
                  </tbody>
               </table><br><p class="para_item">See <a class="links" href="javascript:void(0)" onclick="top.popUpPage('User/index.html?goto=User/14ref37867_31.html&vars=-aux,-home','linkInter','menubar=yes,status=yes,resizable=yes,toolbar=yes,scrollbars=yes,location=no,directories=no');return(false);">&ldquo;Formulation of Dynamic Equations in SubDMAP GMA&rdquo;</a> in the <em>NX Nastran User&rsquo;s Guide</em> for a full explanation. 
               </p>
            </li>
            <li>
               <p class="para_item">If TYPE is &ldquo;G&rdquo; or blank, the damping values gi, etc., are in units of equivalent viscous dampers, as follows: </p>
               <p align="center"><img align="bottom" src="graphics/bulktuv-equ02.gif"></p>
               <p class="para_item">(See <a class="links" href="javascript:void(0)" onclick="top.popUpPage('User/index.html?goto=User/14ref37867_31.html&vars=-aux,-home','linkInter','menubar=yes,status=yes,resizable=yes,toolbar=yes,scrollbars=yes,location=no,directories=no');return(false);">&ldquo;Formulation of Dynamic Equations in SubDMAP GMA&rdquo; </a>in the <em>NX Nastran User&rsquo;s Guide</em>.) If TYPE is &ldquo;CRIT&rdquo;, the damping values gi, etc., are in the units of fraction of critical damping <em>C</em> / <em>C</em><sub class="subscript">0</sub>.  If TYPE is &ldquo;Q&rdquo;, the damping values gi are in the units of the amplification or quality factor, <em>Q</em>.  These constants are related by the following equations: 
               </p>
               <p align="center"><img align="bottom" src="graphics/bulktuv-equ03.gif"></p>
               <p align="center"><img align="bottom" src="graphics/bulktuv-equ04.gif"></p>
            </li>
         </ol>
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