In RecurDyn/RFlex Interface dialog box, select ANSYS.

Figure 1 ANSYS Interface dialog box
ANSYS Interface needs the following four files and these file and output files name automatically set same as emat file name.
•Files
•Result file (*.rst): Contains model information such as node, element, property and the result of CMS or Modal analysis.
•Material file (*.mp): Contains material information such as Young’s modulus, shear modulus and Poisson’s ratio.
•Element Matrices file (*.emat): Contains element matrices information such as element stiffness and mass matrices
•CM File (*.cm): Contains interface node information.
•Units: Changes those units that used in the FE program. This option is used in the current model.
•Output File Name
•RecurDyn/Flex Input File Name: Defines a generated file name with the extension *.rfi.