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      <title>Using the Vibration Wizard</title>
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      <div class="title_topic1" id="xps10_pagetitle">Using the Vibration Wizard</div>
      <hr noshade="true">
      <p class="para_topic">Use the Vibration Wizard to analyze a component's dynamic properties to ensure the design usage of the component will not cause undesirable vibration. The wizard allows you to view a single solid body's mode shapes at its fundamental frequencies. These mode shapes represent the dynamic properties of the component with no loads applied to it. </p>
      <p class="para_topic">You can compare these natural frequencies to the operational frequencies of an anticipated load to predict how the component will respond under that load. If the operational frequencies of the load approach the component's fundamental frequencies, design changes may be necessary to avoid undesirable vibration. </p>
      <p class="para_topic">The frequency response is fixed at &gt; 0.1 Hertz, which prevents the first six 0-Hertz translation and rotation (rigid-body) modes from displaying in your results. The wizard results will include the first 5 modes following the rigid-body modes.</p>
      <p class="para_topic">You can run this wizard in the Modeling, Design Simulation, or Advanced Simulation applications. </p>
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            <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
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               <div class="para_note">
                  <p class="para_note_body">You can open data sets created in the Vibration Wizard only in the Design Simulation or Advanced Simulation applications. </p>
               </div>
            </td>
         </tr>
      </table>
      <div class="title_division">Create a Simulation part file</div>
      <p class="para_division">If you did not create a Simulation part file before starting the Vibration Wizard, you will be prompted to do so when you start the wizard. On the <b class="uiTerm">New Part File</b> page, enter a name for your Simulation file and click <b class="uiTerm">OK</b>.
      </p>
      <div class="title_division">Choose a solid body</div>
      <p class="para_division">The Vibration Wizard works with a single solid body. On the <b class="uiTerm">Welcome to the Vibration Wizard</b> page, select the solid body to evaluate in the NX graphics window and click <b class="uiTerm">Next</b>.
      </p>
      <div class="title_division">Define constraints</div>
      <p class="para_division">Constraints limit structural movement and represent mounts and supports. You must specify at least one constraint.</p>
      <ol type="1" start="1">
         <li>
            <p class="para_item">Choose a constraint type. </p>
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                        <p class="para_td">Constraint Type</p>
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                        <p class="para_td">Description</p>
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                        <p class="para_td"><img align="bottom" src="collection/cae_ico_fixed_constraint.gif" border="0"> <b class="uiTerm">Fixed</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">A fixed constraint does not allow movement in any direction. This is equivalent to welding or gluing the face to a rigid support.</p>
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                        <p class="para_td"><img align="bottom" src="collection/cae_ico_pinned_constraint.gif" border="0"> <b class="uiTerm">Pinned</b></p>
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                        <p class="para_td">You can apply the pinned constraint only to cylindrical faces (&quot;inside&quot; or &quot;outside&quot;). Use it to simulate a pin-through-hole joint. A pinned cylindrical face is free to rotate, but cannot move normal (perpendicular) to the face.</p>
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                        <p class="para_td"><img align="bottom" src="collection/cae_ico_sliding_constraint.gif" border="0"> <b class="uiTerm">Sliding</b></p>
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                     <td colspan="1" rowspan="1">
                        <p class="para_td">A face with a sliding constraint is free to move in any direction along the face, but cannot move normal to the face. This is equivalent to supporting the face on ball bearings. An edge with a sliding constraint is free to slide in a plane. The edge cannot move in a direction normal to the plane of sliding. When you apply a sliding constraint to an edge, you must specify a fixed direction.</p>
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            </table><br></li>
         <li>
            <p class="para_item">Click <b class="uiTerm">Face</b> <img align="bottom" src="collection/cae_ico_select_face.gif" border="0">, <b class="uiTerm">Edge</b> <img align="bottom" src="collection/cae_ico_select_edge.gif" border="0">, or <b class="uiTerm">Point</b> <img align="bottom" src="collection/cae_ico_select_point.gif" border="0"> to select the appropriate geometry to which to apply the constraint on the solid body. The default setting is <b class="uiTerm">Face</b>. 
            </p>
         </li>
         <li>
            <p class="para_item">Select the face, edge, or point on the solid body to which to apply the constraint and then click <b class="uiTerm">Next</b>. 
            </p>
         </li>
         <li>
            <p class="para_item">If you chose the <b class="uiTerm">Sliding</b> constraint type, choose the direction in which the solid body cannot slide and then click <b class="uiTerm">Next</b>.
            </p>
         </li>
         <li>
            <p class="para_item">The wizard returns to the beginning of this step, where you can define additional constraints or click <b class="uiTerm">Next</b> to continue to assign a material.
            </p>
         </li>
      </ol>
      <div class="title_division">Assign a material</div>
      <p class="para_division">Material properties help determine the natural frequencies of the solid body. You must define the material properties of the solid body by selecting from a predefined list of materials. </p>
      <ol type="1" start="1">
         <li>
            <p class="para_item">Select a category from the <b class="uiTerm">Category</b> list to select from lists of metals, plastics, or other materials. 
            </p>
         </li>
         <li>
            <p class="para_item">(Optional) Use the <b class="uiTerm">Filter</b> field to sort the list of materials using words, letters, or numbers, in order to simplify selection. This field allows regular expressions. For example, entering the characters <b class="uiTerm">s*</b> instructs the system to find all materials containing the letter s, such as Steel, Steel-Rolled, etc. 
            </p>
         </li>
         <li>
            <p class="para_item">Select a material from the list. The selected material is automatically assigned to the solid body. </p>
         </li>
         <li>
            <p class="para_item">Click <b class="uiTerm">Next</b>.
            </p>
         </li>
      </ol>
      <div class="title_division">Define the mesh</div>
      <p class="para_division">As part of the meshing step, the solid body is divided into many small <em>elements</em>. Elements are connected at points called <em>nodes</em>. A group of elements is called a <em>mesh</em>. The mesh follows the shape of the solid body, and the behavior of each element is described in the software by mathematical equations. The software finds the analysis solution by adding the individual element solutions.  The wizard mesh uses solid tetrahedral elements.
      </p>
      <ol type="1" start="1">
         <li>
            <p class="para_item">In the <b class="uiTerm">Element</b> field, enter a size for the individual elements or click <b class="uiTerm">Calculate Element Size</b> to allow the wizard to calculate an appropriate element size. The default value is the calculated element size.
            </p>
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                  <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
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                     <div class="para_note">
                        <p class="para_note_body">The accuracy of a finite element solution improves as you reduce the element size. However, the solution time and computer resources needed to run the analysis also increase when more elements are used. </p>
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         </li>
         <li>
            <p class="para_item">Click <b class="uiTerm">Next</b> to generate the mesh and move on to the next step.
            </p>
         </li>
      </ol>
      <p class="para_division">The wizard creates all meshes directly on the model's polygon geometry. It stores all meshes and mesh related data, such as the mesh's material properties, in the FEM file.</p>
      <div class="title_division">Perform the simulation</div>
      <p class="para_division">Click <b class="uiTerm">Perform Simulation</b> <img align="bottom" src="collection/cae_ico_perform_sim.gif" border="0"> to start the NX Nastran solver. During the solution process, messages are displayed in the <b class="uiTerm">Information</b> window. The computer should beep when the solution is complete. 
      </p>
      <p class="para_division">If the analysis fails to run, errors will appear in the <b class="uiTerm">Information</b> window. Most analysis failures are ultimately due to geometry problems. Examine the geometry for fundamental problems such as tiny faces, sliver faces, and self-intersecting faces. Try to simplify or alter the model to eliminate these problems. 
      </p>
      <p class="para_division">After the solution is complete, click <b class="uiTerm">Next</b> to move on to the <b class="uiTerm">View Results</b> page.
      </p>
      <div class="title_division">View solution results</div>
      <p class="para_division">The results of the analysis are displayed.</p>
      <p class="para_division">The <b class="uiTerm">View Results</b> page allows you to display plots of Modes 1&ndash;5 (the wizard is fixed to display only the first 5 modes that occur after the rigid-body modes). 
      </p>
      <p class="para_division">Click one of the five mode shape icons to display a graphical simulation of the deformation the solid body will undergo when the frequency of a force acting on it approaches this natural frequency. The frequency information for the mode is displayed at the top of the graphics window along with the simulation. For example, &ldquo;Deformation : Mode 1 : 2.173e+002 Hz, Displacement &ndash; Nodal.&rdquo;</p>
      <p class="para_division">Click <b class="uiTerm">Play</b> <img align="bottom" src="collection/mode_shape_play.gif" border="0"> to animate the displayed modal shape. 
      </p>
      <p class="para_division">When you are finished viewing the mode shapes, click <b class="uiTerm">Next</b> to move on to the <b class="uiTerm">Report Generation</b> page.
      </p>
      <div class="title_division">Generate reports</div>
      <p class="para_division">You can generate an HTML report with images and data generated during the simulation.</p>
      <p class="para_division">To generate a report, including images of each mode shape:</p>
      <ol type="1" start="1">
         <li>
            <p class="para_item">Close the <b class="uiTerm">Information</b> window if it is still open from the previous step.
            </p>
         </li>
         <li>
            <p class="para_item">Click <b class="uiTerm">Create Images</b> <img align="bottom" src="collection/capture_mode_shape_image.gif" border="0">. 
            </p>
            <p class="para_item">The wizard captures images of each mode shape.</p>
         </li>
         <li>
            <p class="para_item">Click <b class="uiTerm">Display Report</b> <img align="bottom" src="collection/display_report.gif" border="0">.
            </p>
            <p class="para_item">A report displays in your Web browser containing the images of the mode shapes, your material and mesh properties, constraints, and the modal frequencies of the solid body.</p>
         </li>
         <li>
            <p class="para_item">Click <b class="uiTerm">Next</b> to move on to the <b class="uiTerm">Finish</b> page. 
            </p>
         </li>
      </ol>
      <div class="title_division">Finish the simulation</div>
      <p class="para_division">At this point, the process is complete. Click the <b class="uiTerm">Save</b> button to save your FEM file and Simulation results. Click <b class="uiTerm">Finish</b> to close the wizard. 
      </p>
      <p class="para_division">You can open the Simulation file in the Design Simulation or Advanced Simulation applications for additional analysis.</p>
      <ol type="1" start="1">
         <li>
            <p class="para_item">Choose <b class="uiTerm">Window</b> &rarr; &lt;simulation_file_name&gt;.sim to open the Simulation file in the Design Simulation or Advanced Simulation application.
            </p>
            <table border="0">
               <tr>
                  <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
                  <td valign="bottom" align="left" width="100%">
                     <div class="para_note">
                        <p class="para_note_body">You can open data sets created in the Vibration Wizard only in the Design Simulation or Advanced Simulation applications. </p>
                     </div>
                  </td>
               </tr>
            </table>
         </li>
         <li>
            <p class="para_item">Click <b class="uiTerm">Enter Post Processing</b> <img align="bottom" src="collection/cae_ico_enter_post.gif" border="0">.
            </p>
         </li>
      </ol>
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