Improved free-interface substructures representation method

The purpose of this paper is to present a method of free interface substructuring. It shows substructure mass and stiffness coupling in the condensed model. Reduction is performed by means of a new consistent transformation, which leads to a condensed model without junction coordinates. We also intend to show a variant which allows a condensed model to be obtained in physical coordinates. Finally, a second level modal condensation in physical coordinates is presented, so that the resulting model may be reduced even more. Such a model allows direct comparison between measurements and calculations.