A beam model based longitudinal-lateral-torsional integrated modeling technique for launch vehicle

In traditional structure dynamics analysis for launch vehicle, the coupling effects among longitudinal mode, lateral mode and torsional mode cannot be reflected by using different models in longitudinal and lateral direction. To deal with the problem, a partial structure modeling method for strap-on booster and coupled mass approach is proposed to simulate of the binding stiffness and different effects of liquid propellants in lateral, longitudinal and torsional directions. The technique extends applicability of beam model approach and makes the objective of longitudinal-lateral-torsional integrated dynamics modeling of launch vehicle achieved. The achievement provides a effective approach for researching the dynamics of strap-on launch vehicle, which has serried modes and prominent longitudinal-lateral-torsional coupling effects.