Semianalytical Model for Dynamic Analysis of Missile Vertical Cold Launch

Abstract

To quickly determine the dynamic characteristics of a missile excited by wind load during a vertical cold launch, a semianalytical model has been established by using the transfer matrix method and modal superposition approach, where the missile is simplified as a segmental Timoshenko beam and the adapter is equivalent to a spring with compressive and flexural stiffness. Then, the semianalytical model is verified by a finite element method and used to analyze the effects of wind load, thrust deviation, and the adapter’s elastic modulus on missile launch. The fact validates that the semianalytical model is effective and feasible, as well as more efficient, as compared with the finite element model, which is beneficial to perform the aforementioned influence analysis. The research proves that wind load has almost no effect on the missile’s vertical displacement but makes an obvious influence on the horizontal displacement and yaw angle. The missile rises more slowly, and the horizontal motion is delayed with less thrust; consequently, the horizontal displacement and yaw angle are increased when the missile reaches a specified altitude. The horizontal displacement and yaw angle are decreased with the adapter’s elastic modulus increased when the adapter’s assembly stress remains constant.