Transient Solutions of Time-Variant Structural Systems

ASD personnel have also pioneered a method of simulating transient events in which the structural system modal properties are changing in time (see ASD Journal Publications), e.g., a launch vehicle modal properties continual change during ascent due to the continual loss of mass in the propulsion system. In this example, the propellant mass is treated as applied inertial forces to the launch vehicle’s invariant modal properties. Again, the principles of component modal synthesis is strictly enforced to yield accurate system modal properties throughout the transient event.