The Contact Tool enables you to examine contact conditions on an assembly both before loading, and as part of the final solution to verify the transfer of loads (forces and moments) across the various contact regions. The Contact Tool is an object you can insert under a Connections object for examining initial contact conditions, or under a Solution or Solution Combination branch object for examining the effects of contact as part of the solution. The Contact Tool enables you to conveniently scope contact results to a common selection of geometry or contact regions. In this way, all applicable contact results can be investigated at once for a given scoping.
A Contact Tool is scoped to a given topology, and there exist two methods for achieving this: the method and the method. Under the method, the Contact Tool is scoped to one or more contact regions. Under the method, the Contact Tool can be scoped to any geometry on the model. Regardless of the method, the scoping on the tool is applied to all results grouped under it.
To use a Contact Tool, prepare a structural analysis for an assembly with contacts. You then use either the or scoping method for results.
Important: If you are importing PCB traces from External Data, the trace materials must include the necessary structural properties to generate initial contact results, or the application generates an error. See the ECAD Analysis using Trace Mapping section for more information.
Evaluating Initial Contact Conditions
Note: To calculate initial contact results, the Contact Tool assumes small deflection. This assumption affects the resulting pinball radius of the scoped contacts if their Pinball Region property is set to .
To evaluate initial contact conditions using the Worksheet method:
Insert a Contact Tool in the Connections folder ( from the Connections Context tab or right-click the Connections object and then select > ). The tool is inserted and includes a default Initial Information child object.
In the Details of the Contact Tool, ensure that (the default) is selected in the Scoping Method field. The appears. Scoped contact regions are those that are checked in the table.
You can modify your selection of contact regions in the using the following procedures:
To add or remove pre-selected groups of contact regions (, , or ), use the drop-down menu and the corresponding buttons.
To add any number of contact regions, you can also drag-drop or copy-paste any number of contact regions from the Connections folder into the Contact Tool in the Tree View. Also, one or more contact regions can be deleted from the Contact Tool worksheet by selecting them in the table and pressing the Delete key.
To change the Contact Side of all contact regions, choose the option in the drop-down menu (, , or from the drop-down menu and click the button).
To change an individual Contact Side, click in the particular cell and choose , , or from the drop-down menu.
Add contact result objects of interest under the Contact Tool folder using the option of the Contact Tool Context tab. Or, you can right-click the tool and select > [desired result]. The specific contact result objects are inserted.
Obtain the initial contact results using a right mouse button click the Contact object, or Contact Tool object, or any object under the Contact Tool object, then choosing from the context menu. Results are displayed as follows:
When you highlight the Initial Information object, a table appears in the Worksheet that includes initial contact information for the contact regions that you specified in step 2 above. You can display or hide the various columns in the table. The table rows display in various colors that indicate the detected contact conditions. A brief explanation of each color is provided in the legend that is displayed beneath the table. Copies of the legend explanations are presented below in quotes, followed by more detailed explanations.
Red: "The contact status is open but the type of contact is meant to be closed. This applies to bonded and no separation contact types."
Workbench has detected an open contact Status condition, which is invalid based on the definitions of Bonded and No Separation contact types. It is very likely that the model will not be held together as expected. The geometry of the contact may be too far apart for the closed condition to be satisfied. Review of the Contact Region definition is strongly recommended.
Yellow: "The contact status is open. This may be acceptable."
Workbench has detected an open contact Status condition on a nonlinear contact type, Frictionless, Rough, or Frictional, which is probably acceptable under certain conditions as stated in their descriptions.
If the Status is Far Open, the Penetration and the Gap will be set to zero even though the Resulting Pinball is non-zero.
Note: Currently, contact results are not saved to results (.rst) file for all contact elements that are outside the pinball region to optimize the file size. Results for Far-field contact elements were reported as zero in prior releases.
Orange: "The contact status is closed but has a large amount of gap or penetration. Check penetration and gap compared to pinball and depth."
Workbench has detected that any of the following contact results are greater than 1/2 of the Resulting Pinball, or greater than 1/2 of the Contact Depth: Gap, Penetration, maximum closed Gap, maximum closed Penetration. This could lead to poor results in terms of stiffness of the contacting interface. Ansys recommends that you alter the geometry to reduce the gap or penetration.
Gray: "Contact is inactive. This can occur for MPC and Normal Lagrange formulations. It can also occur for auto asymmetric behavior."
Refer to the individual descriptions for the MPC and Normal Lagrange formulations, and the description for Auto Asymmetric behavior.
Note: The "not applicable" designation, N/A appears in the following locations and situations:
All result columns when the contact pair is inactive (row is gray, or Inactive appears under the Status column).
The Geometric Gap column for Frictionless , Rough , or Frictional contact Types and an Interface Treatment set to Add Offset , .
When you highlight any of the contact result objects, the Geometry tab appears and displays the graphical result for the contact regions that you specified in step 2 above.
To evaluate initial contact conditions using the Geometry Selection method:
Select one or more bodies that are in contact.
Insert a Contact Tool in the Connections folder ( from the Connections Context tab or right-click the Connections folder and then select > ). The tool is inserted and includes a default Initial Information child object.
Note: The scoping of the Initial Information object is only available using the Worksheet method. Selecting bodies as in Step 1 above has no effect on Initial Information results.
In the Details of the Contact Tool, select in the Scoping Method field. The bodies that you selected in step 1 are highlighted in the Geometry tab.
Add contact result objects of interest under the Contact Tool folder using the option of the Contact Tool Context tab. Or, you can right-click the tool and select > [desired result]. The specific contact result objects are inserted.
Obtain the initial contact results using a right mouse button click the Contact object, or Contact Tool object, or any object under the Contact Tool object, then choosing from the context menu. When you highlight any of the contact result objects, the Geometry tab appears and displays the graphical result for the bodies that you selected in step 1.
Evaluating Contact Conditions After Solution
Note: The default method will be the last one that you manually chose in the Scoping Method drop-down menu. If you have already selected geometry, the Scoping Method field automatically changes to . The default however will not change until you manually change the Scoping Method entry.
To evaluate contact conditions after solution using the Worksheet method:
Insert a Contact Tool from the Toolbox drop-down menu on the Solution Context tab or right-click the Solution folder and then select > > ). The tool is inserted and includes a default Status child object.
In the Details, select in the Scoping Method field. The appears. Scoped contact regions are those that are checked in the table.
You can modify your selection of contact regions in the using the following procedures:
To add or remove pre-selected groups of contact regions (, , or ), use the drop-down menu and the corresponding buttons.
To add any number of contact regions, you can also drag-drop or copy-paste any number of contact regions from the Contact folder into the Contact Tool in the Tree View. Also, one or more contact regions can be deleted from the Contact Tool worksheet by selecting them in the table and pressing the Delete key.
To change the Contact Side of all contact regions, choose the option in the drop-down menu (, , or from the drop-down menu and click the button).
To change an individual Contact Side, click in the particular cell and choose , , or from the drop-down menu.
Add more contact results as needed in the Contact Tool folder ( from the Contact Tool Context tab, or right mouse button click Contact Tool, then ).
Solve database. Upon completion, you will see contact results with the common scoping of the Contact Tool.
To evaluate contact conditions after solution using the Geometry Selection method:
Select one or more bodies that are in contact.
Insert a Contact Tool from the Toolbox drop-down menu on the Solution Context tab or right-click the Solution folder and then select > > ). The tool is inserted and includes a default Status child object. Because you have already selected one or more bodies, is automatically set in the Scoping Method field within the Details.
Add more contact results as needed to the Contact Tool folder either by right-clicking on the object and selecting > [desired result] or using the options of the Contact Tool Context tab.
Solve database. Upon completion, you will see contact results with the common scoping of the Contact Tool.
The configuration of the Contact Tool, in particular the location (Solution vs Solution Combination) and the scoping method, affects the availability of results. A Contact Tool in the Solution Combination folder has the limitation that it supports only pressure, frictional stress, penetration and distance.
- Limitation
Note that when the Contact Tool, whether inserted under the Connection folder or the Solution object, has a limitation for coincident contact elements. If you have 1) two contact conditions, and each condition shares elements from one of the bodies, and 2) in the Worksheet you have selected only one row for the contact conditions, the application uses the element data for both contact conditions to produce the Contact Tools Results content. The numerical values at the shared node are contributed by all the contact elements that touch it.
To make sure that you have correct contact results, 1) obtain User Defined results from the Available Solution Quantities of the Solution Summary Worksheet and 2) scope the User Defined results using the Result File Item and Element Type IDs options. This enables you to specify only the desired contact elements. You can obtain Element Type IDs from the Material and Element Type Information option of the Solution Summary Worksheet.