VIVANA Calculation Parameters VIVANA calculated the response of a slender beam structure in a current, excited by vortex shedding. Response to cross-flow and in-line excitation can be calculated separately. VIVANA is linked to the analysis program system RIFLEX and may be used for analysis of various marine structures such as tensioned and flexible risers, anchor lines, umbilicals, tendons, pipelines during installation and free spanning pipelines. The following limitations apply to the RIFLEX model: All cross-sections must have mass and radius of gyration Bar elements are not supported Only 2D current profiles may be used The current profile to be used must be directed perpendicular or parallel to the plane of the structure. The current profile to be used is selected in the static analysis. The current loads should normally be applied in the static analysis. The current scaling factor specified to STAMOD is applied.