Specifying thermal conductance for thermal contact property options

From the main menu bar, select InteractionPropertyCreate.

In the Create Interaction Property dialog box that appears, do the following:

• Name the interaction property. For more information about naming objects, see Using basic dialog box components.

• Select the Contact type of interaction property.

Click Continue to close the Create Interaction Property dialog box.

From the menu bar in the contact property editor, select ThermalThermal Conductance.

The Edit Contact Property dialog box appears.

In the editor that appears, click the arrow to the right of the Definition field, and select an option for defining thermal conductance:

• Select Tabular to enter data relating thermal conductance to the clearance or pressure between the contact surfaces.

• Select User-defined to define thermal conductance in user subroutine GAPCON. If you select this option, skip to Step 9.

Indicate whether you want to define thermal conductance as a function of the clearance between the surfaces, the contact pressure between the surfaces, or both.

If you want to define thermal conductance as a function of clearance, display the Clearance Dependency tabbed page, and do the following:

1. Toggle on Use temperature-dependent data if the data are dependent on temperature.
2. Toggle on Use mass flow rate-dependent data (Standard only) if the data are dependent on the average mass flow rate per unit area, $\overline{\left|\dot{m}\right|}$.
3. Click the arrows to the right of the Number of field variables field to specify the number of field variables on which the data depend.
4. In the data table, define thermal conductance as a function of gap clearance.

   The tabular data must start at zero clearance (closed gap) and define thermal conductance as clearance increases. You must provide at least two pairs of points. The value of thermal conductance drops to zero immediately after the last data point, so there is no conductance when the clearance is greater than the value corresponding to the last data point. If conductance is not also defined as a function of contact pressure, it will remain constant at the zero clearance value for all pressures.

If you want to define thermal conductance as a function of contact pressure, display the Pressure Dependency tabbed page, and do the following:

1. Toggle on Use temperature-dependent data if the data are dependent on temperature.
2. Toggle on Use mass flow rate-dependent data (Standard only) if the data are dependent on the average mass flow rate per unit area, $\overline{\left|\dot{m}\right|}$.
3. Click the arrows to the right of the Number of field variables field to specify the number of field variables on which the data depend.
4. In the data table, define thermal conductance as a function of contact pressure at the interface.

   The tabular data must start at zero contact pressure (or, in the case of contact that can support a tensile force, the data point with the most negative pressure) and define thermal conductance as pressure increases. The value of thermal conductance remains constant for contact pressures outside of the interval defined by the data points. If conductance is not also defined as a function of clearance, it is zero for all positive values of clearance and discontinuous at zero clearance

Click OK to create the contact property and to exit the Edit Contact Property dialog box. Alternatively, you can select another contact property option to define from the menus in the Edit Contact Property dialog box.