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      <title>Using the Stress Wizard</title>
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      <div class="title_topic1" id="xps10_pagetitle">Using the Stress Wizard</div>
      <hr noshade="true">
      <p class="para_topic">The Stress Wizard allows you to evaluate the safety factor of a single solid body to ensure that the yield strength of the material is not exceeded. You can run this wizard in the Modeling, Design Simulation, or Advanced Simulation applications. </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 Stress 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 Stress Wizard, you will be prompted to do so when you start the wizard. In 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 Stress Wizard simulates a load on a single solid body. On the <b class="uiTerm">Welcome to the Stress 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">Apply a load</div>
      <ol type="1" start="1">
         <li>
            <p class="para_item">On the <b class="uiTerm">Loads</b> page, choose the appropriate load type. 
            </p>
            <table border="0" cellpadding="4" cellspacing="2" width="95%" align="center">
               <colgroup span="1">
                  <col span="1" width="32*">
                  <col span="1" width="160*">
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               <thead>
                  <tr bgcolor="silver">
                     <td colspan="1" rowspan="1" valign="top">
                        <p class="para_td">Load Type</p>
                     </td>
                     <td colspan="1" rowspan="1" valign="top">
                        <p class="para_td">Description</p>
                     </td>
                  </tr>
               </thead>
               <tbody valign="top">
                  <tr bgcolor="#F0F0F0">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><img align="bottom" src="collection/cae_ico_force.gif" border="0"> <b class="uiTerm">Force</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">A load applied to geometry (curves, points, mesh points, polygon faces, or polygon edges) and then mapped to nodes.</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><img align="bottom" src="collection/cae_ico_torque.gif" border="0"> <b class="uiTerm">Torque</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">A tangential load that can be applied to a cylindrical face or circular edge (curves, polygon faces, or polygon edges). A torque load is automatically oriented to the normal axis of the cylindrical face or circular edge. When you apply a torque to many faces, each face or edge uses its own normal axis for orientation.</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><img align="bottom" src="collection/cae_ico_pressure.gif" border="0"> <b class="uiTerm">Pressure</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">A uniformly applied load that can be defined in any direction for polygon faces.</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><img align="bottom" src="collection/cae_ico_bearing.gif" border="0"> <b class="uiTerm">Bearing</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">A distributed force on the nodes of a cylindrical face or cylindrical edge within the region defined by an angle. Uses the element normal to orient the load. Typical conditions that can be modeled with bearing loads are roller bearings, gears, cams and rolling wheels. Bearing loads are not distributed uniformly on geometry. Instead, the bearing load varies sinusoidally between 0 and 180 degrees.</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><img align="bottom" src="collection/cae_ico_gravity.gif" border="0"> <b class="uiTerm">Gravity</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">The force acting on a body due to gravity. The force is calculated by multiplying the body's mass by the gravitational acceleration. The direction and value of the gravitational acceleration can be changed if necessary. The mass is automatically calculated by the software.</p>
                     </td>
                  </tr>
               </tbody>
            </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 load on the solid body. The default setting is <b class="uiTerm">Face</b>. Some load types cannot be applied to certain geometry types.
            </p>
            <table border="0" cellpadding="2" cellspacing="4" width="346" align="center">
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                  <col span="1" width="57*">
                  <col span="1" width="135*">
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               <tbody>
                  <tr bgcolor="silver">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">This Load Type..</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">Supports this geometry...</b></p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Force</p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Face, edge, or point</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Torque</p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Circular edge</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Pressure</p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Face</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" height="26" rowspan="1">
                        <p class="para_td">Bearing</p>
                     </td>
                     <td colspan="1" height="26" rowspan="1">
                        <p class="para_td">Circular face or circular edge</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Gravity</p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Solid body</p>
                     </td>
                  </tr>
               </tbody>
            </table><br><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">Edge loads are less accurate than face loads in certain situations. Consult an experienced finite element analyst if you are unsure about the use of edge loads.</p>
                     </div>
                  </td>
               </tr>
            </table>
         </li>
         <li>
            <p class="para_item">Select the face, edge, or point on the solid body to which to apply the load and then click <b class="uiTerm">Next</b>. 
            </p>
         </li>
         <li>
            <p class="para_item">Enter the load parameters according to the type of load you chose.</p>
            <table border="0" cellpadding="2" cellspacing="4" width="95%" align="center">
               <colgroup span="1">
                  <col span="1" width="28*">
                  <col span="1" width="166*">
               </colgroup>
               <tbody>
                  <tr bgcolor="silver">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">For this Load Type...</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">Enter this data...</b></p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">Force</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">Click <b class="uiTerm">Force Vector</b> <img align="bottom" src="collection/cae_ico_force_vector.gif" border="0"> to define a force load with a magnitude and a single direction. 
                        </p>
                        <p class="para_td">&mdash;or&mdash;</p>
                        <p class="para_td">Click <b class="uiTerm">Direction Components</b> <img align="bottom" src="collection/cae_ico_component_force.gif" border="0"> to enter a force magnitude for each of the X, Y, and Z components in the coordinate system.
                        </p>
                        <p class="para_td">Enter the magnitude of the force in the <b class="uiTerm">Force</b> field (if you clicked <b class="uiTerm">Force Vector</b>) or in the <b class="uiTerm">Fx</b>, <b class="uiTerm">Fy</b>, and <b class="uiTerm">Fz</b> fields (if you clicked <b class="uiTerm">Direction Components</b>). Select the force units from the list.
                        </p>
                        <p class="para_td">If you clicked <b class="uiTerm">Force Vector</b>, use the <b class="uiTerm">Direction Vector</b> list to specify the direction of the force. If you clicked <b class="uiTerm">Inferred Vector</b>, select geometry that is oriented in the direction for the force.
                        </p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">Torque</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">In the <b class="uiTerm">Torque</b> field, enter the magnitude of the torque. Select the torque units from the list.
                        </p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">Pressure</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">In the <b class="uiTerm">Pressure</b> field, enter the magnitude of the pressure. Select the pressure units from the list.
                        </p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">Bearing</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">In the <b class="uiTerm">Bearing Load</b> field, enter the magnitude of the load. Select the bearing load units from the list. 
                        </p>
                        <p class="para_td">Use the <b class="uiTerm">Direction Vector</b> list to specify the direction of the load. If you clicked the <b class="uiTerm">Inferred Vector</b> option, select geometry that is oriented in the direction for the load.
                        </p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0" valign="top">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><b class="uiTerm">Gravity</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <p class="para_td">In the <b class="uiTerm">Gravity</b> field, enter the magnitude of gravity. Select the gravity units from the list.
                        </p>
                        <p class="para_td">Use the <b class="uiTerm">Direction Vector</b> list to specify the direction of the load. If you clicked the <b class="uiTerm">Inferred Vector</b> option, select geometry that is oriented in the direction for the load.
                        </p>
                     </td>
                  </tr>
               </tbody>
            </table><br></li>
         <li>
            <p class="para_item">Click <b class="uiTerm">Next</b>. The wizard returns to the beginning of this step, where you can choose a geometry type to apply additional loads or click <b class="uiTerm">Next</b> to apply constraints.
            </p>
         </li>
      </ol>
      <div class="title_division">Define constraints</div>
      <p class="para_division">Constraints limit structural movement and represent mounts and supports.</p>
      <ol type="1" start="1">
         <li>
            <p class="para_item">Choose a constraint type. </p>
            <table border="0" cellpadding="4" cellspacing="2" width="95%" align="center">
               <colgroup span="1">
                  <col span="1" width="33*">
                  <col span="1" width="160*">
               </colgroup>
               <thead>
                  <tr bgcolor="silver">
                     <td colspan="1" rowspan="1" valign="top">
                        <p class="para_td">Constraint Type</p>
                     </td>
                     <td colspan="1" rowspan="1" valign="top">
                        <p class="para_td">Description</p>
                     </td>
                  </tr>
               </thead>
               <tbody valign="top">
                  <tr bgcolor="#F0F0F0">
                     <td colspan="1" rowspan="1">
                        <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>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><img align="bottom" src="collection/cae_ico_pinned_constraint.gif" border="0"> <b class="uiTerm">Pinned</b></p>
                     </td>
                     <td colspan="1" rowspan="1">
                        <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 to the face.</p>
                     </td>
                  </tr>
                  <tr bgcolor="#F0F0F0">
                     <td colspan="1" rowspan="1">
                        <p class="para_td"><img align="bottom" src="collection/cae_ico_sliding_constraint.gif" border="0"> <b class="uiTerm">Sliding</b></p>
                     </td>
                     <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>
                     </td>
                  </tr>
               </tbody>
            </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 determine how structures behave under stress. 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 software 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>
            <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">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>
                     </div>
                  </td>
               </tr>
            </table>
         </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 using fringe plots. These are special 3D color plots that clearly display the value and shape of the stress and displacement fields.</p>
      <p class="para_division">The <b class="uiTerm">View Results</b> page allows you to display plots of Safety Factor (structural performance), Displacements, and Stresses.
      </p>
      <ul>
         <li>
            <p class="para_item"><b class="uiTerm">Displacement</b> <img align="bottom" src="collection/cae_ico_displacement.gif" border="0"> &mdash; Displays deformation. The maximum deformation is indicated above the spectrum legend. The display of displacements is exaggerated for clarity. The scale can be changed using the <b class="uiTerm">Display Options</b> menu. 
            </p>
         </li>
         <li>
            <p class="para_item"><b class="uiTerm">Stress</b> <img align="bottom" src="collection/cae_ico_stress.gif" border="0"> &mdash; Provides a 3D display of the Von Mises stress in the structure. The Von Mises stress accounts for both axial and shear stresses, and is useful when evaluating potential for failure.
            </p>
         </li>
         <li>
            <p class="para_item"><b class="uiTerm">Safety Factor</b> <img align="bottom" src="collection/cae_ico_structural.gif" border="0"> &mdash; Uses material yield (or fracture) data, and a safety factor, to classify areas of the part as &quot;safe,&quot; &quot;exceeds safety factor,&quot; or &quot;failure.&quot; The safety factor is set to 2.0. A region is classified as &quot;safe&quot; if the stresses are less than the yield stress (or fracture stress) divided by the safety factor.
            </p>
         </li>
      </ul>
      <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 stress plot. 
      </p>
      <p class="para_division">When you are finished viewing the solution results, 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 the stress, displacement, and safety factor plots:</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 plot.</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 stress, displacement, and safety factor plots, your material and mesh properties, constraints, loads, and other information about the model.</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.sim&gt; 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 Stress 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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