Solids and Assemblies: Support and contact boundary conditions

Support and contact boundary conditions are defined to surface of part.

Set the coordinate system of the surface

1. Select surfaces.
2. Press Local Coordinate System checkbox from the ribbon tab.
   • When the checkbox is checked, the coordinate system of the surfaces is the local coordinate system of the surface.
   • When unchecked, the coordinate system is the global coordinate system of 3d model.

The degrees of freedom are defined in the coordinate system of the surface.

Local coordinate system is denoted by letter L in the Supports branch of study tree.

Define contact surface

1. Select surfaces.
2. Set Local Coordinate System for surfaces.  
3. Select Contact from contextual ribbon tab.
   

Set the degrees of freedom for surfaces

1. Select surfaces.
   
2. Press

   

   X-translation, Y tai Z to change the support definition of certain degree of freedom.
   
   • Boundary condition definitions are set always in the selected coordinate system of the surface.
   • Boundary condition options and their descriptions for non-contact surface are listed in the table below.

Symbol in ribbon tab	Symbol in study tree	Boundary condition definition	Description
	0	Fixed to connecting faces (default)	The degree of freedom for surface is fixed to connecting faces. The connecting faces must belong to active study. If connecting faces do not exist the degree of freedom is free.
	1	Fixed at location	The degree of freedom for surface is fixed at location. Its displacement is zero in the solution.
	2	Free	The degree of freedom surface is freed from connecting faces and location.

• 
  
  • Boundary condition options and their descriptions for contact surface are listed in the table below.

Symbol in ribbon tab	Symbol in study tree	Boundary condition definition	Description
	0	Fixed to connecting faces	For X and Y coordinate The degree of freedom for surface is fixed to connecting faces For Z coordinate (The surface normal) The degree of freedom for surface is fixed to connecting faces in the initial state of contact iteration
	2	Free	For X and Y coordinate The degree of freedom for surface is freed from connecting faces For Z coordinate (The surface normal) The degree of freedom for surface is freed from connecting faces in the initial state of contact iteration

Note!

The boundary condition definition for Z coordinate of contact surface should not have effect on results. It only modifies the initial state of contact iteration.

Define boundary conditions with preset

1. Select surfaces from 3d model.
2. Select preset from

   

    Presets drop-down menu of contextual ribbon tab.
   
   • The preset function changes boundary condition definitions for all coordinate system directions (X, Y and Z) simultaneously.