Nose deflection control is a new concept of fast response control model.The partial nose of projectile deflects a certain angle relative to the axis of projectile body and then pressure difference emerges on the windward and leeward sides of warhead.Consequently,aerodynamic control force is generated.This control way has high control efficiency and very good application prospects in the ammunition system.Nose deflection actuator based on smart material and structure enables projectile body morphing to obtain additional aerodynamic force and moment,changes the aerodynamic characteristics in the projectile flight process,produces the corresponding balance angle and sideslip angle resulting in motor overload,adjusts flight moving posture to control the ballistics,finally changes shooting range and improves firing accuracy.In order to study characteristics of self-adaptive control projectile,numerical simulations are conducted by using fluid dynamics software ANSYS FLUENT for stabilized rocket projectile.The aerodynamic characteristics at different nose delectation angles,different Mach numbers and different angles of attack are obtained and compared.The results show that the nose deflection control has great influence on the head of rocket projectile,and it causes the asymmetry of the flow field structure and the increase of pressure differences of the warhead on the windward and leeward surface,which results in a larger lift.Finally,ballistics experiments are done for verification.The results can offer theoretical basis for self-adaptive rocket projectile design and optimization and also provide new ideas and methods for field smart ammunition research.
