Coupled Dynamic Load Analsyis with Different Component Damping of the Substructures

Paper number

IAC-08.C2.3.3

Author

Dr. Andreas Rittweger, EADS Astrium Space Transportation, Germany

Coauthor

Mr. Kiyoumars Abdoly, EADS Astrium Space Transportation, Germany

Coauthor

Dr. Stefan Dieker, Ingenieurbuero Stefan Dieker, Germany

Coauthor

Dr. Jochen Albus, EADS Space Transportation GmbH, Germany

Year

2008

Abstract

The coupled dynamic load analysis of space transportation systems like Ariane 5 or the Space Shuttle uses the coupling of substructures (solid propellant booster, liquid propellant stages, payloads) to build the mathematical model of the equation of motion. State of the art is to couple the undamped mass and stiffness matrices of the substructures and to introduce modal damping for the coupled system by experience.

On the other hand the modal damping of the substructures is known by substructure testing under certain boundary conditions. In general each mode of the substructure has different damping. The coupling of the substructures should consider the different component damping consequently in the coupled model in order to give realistic damping of the coupled system. 

In the past, several approaches were implemented in order to condense and couple the mathematical models of damped substructures (Full Triple Matrix Product, Two Step Method, Hruda-Benfield, ATV-Method). However, for general purposes none of them is satisfactory.

The new method presented here allows for a consequent introduction of damped substructures. It includes a coherent condensation, coupling and coupled load analysis. The presented approach deals with nonproportional damped systems and its condensation as well as simplified procedures for systems with small damping.

Simplified examples for understanding the phenomena and the application of the method to real spacecraft models like Ariane 5 and the ATV are shown. The presented results show the benefit of the new method for realistic results. 

Abstract document

IAC-08.C2.3.3.pdf

Manuscript document

IAC-08.C2.3.3.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.