Aeroelastic stability analysis of a pyrotechnic separation plate in subsonic airflow

Abstract

Pyrotechnic separation devices are widely used in aerospace engineering. In separation process, the pyrotechnic separation device breaks into several parts, and the velocity of the separated structure changes intricately, which make the pyrotechnic separation device and the external airflow a complex fluid-structure coupling system. Since the stability of the structure is crucial for the safety, it is necessary to investigate the aerodynamic stability of the pyrotechnic separation device interacting with surrounding airflow. In the present study, the aeroelastic stability of a pyrotechnic separation plate in axial subsonic airflow is studied. The velocity of the residual plate is derived from the momentum theorem. The dynamic model of the pyrotechnic separation plate in subsonic airflow is established based on the linear potential flow theory and the von Kármán plate theory. The effects of the residual length, the pyrotechnic explosion strength and the separation velocity on the stability of the plate are investigated, and the vibration properties of the plate are discussed. From the results, the plate loses stability rapidly when it subjects to the explosion, and restores stability under the negative pressure. The displacement jumping phenomenon is observed. The amplitude of the plate in unstable period increases rapidly, which may cause damage to the structure.