| For improving performance of current armored weapon system in the battlefield environment,exploration on realizing high-efficiency damages on the armored targets by the rotational projectile which fly along the straight trajectory.After proposing a type of empennage whose structure twists along the span direction and applying it to the hedgehopping terminal-sensitive projectile,detailed studies on empennage dynamic characteristics,aerodynamic numerical simulation,flight dynamics modeling of high-speed rotational empennage-stabilized projectile,steady scanning characteristics,hit probability and so on are performed.The results can provide reference for overall design,aerodynamic optimization,and stability analysis and effectiveness analysis of terminal sensitive projectiles.Considering the projectile-empennage combination with the twisted empennage as the study object,and its operation principle is introduced first.Twist rate and mean attack angle are used to reflect the structural characteristics of the twisted empennage,and rolling dynamics equations are established,so that influence laws of structural sizes on the rotational speed are further obtained,and match of flying speed and rotational speed is realized;numerical simulation on the empennage impact is performed using LS-DYNA,and the stress curves on the dangerous points are obtained;discrete solution on the high-order aeroelastic equations is performed using differential quadrature method(DQM),so that influences of empennage sizes on the basic frequency are found,which provides reference to avoid empennage strength fracture due to resonance.Secondly,numerical simulation and experiments on the aerodynamic characteristics of the hedgehopping terminal-sensitive projectile are performed,and simulation method is also introduced.By solving the projectile model,aerodynamic parameters are obtained and further analysis on the mechanism of rotational speed increase and drag reduction and Magnus effect is performed;in the wind tunnel experiments,the influence law of twist rate on the projectile aerodynamic parameters is found,matching results by numerical simulation well.Study methods used can also provide guidance for the overall design and optimization of the hedgehopping terminal-sensitive projectile.After that,by considering influences of dynamic unbalance,wind and other factors,6-D dynamic equations of this projectile under detailed complicated conditions are established and worked out,and ballistic parameter histories are obtained;further,angular motion equations are developed and stability analysis is performed,indicating that increasing static moment,weakening Magnus effects and reducing dynamic unbalance can support projectile flight stability;by the coordinate transformation theory,the scanning curve equation is established and solved with flight dynamic equations,so that the scanning zone of this projectile is found,and further analysis on influences from the initial speed and angle of firing on the steady scanning characteristics is also performed.Finally,based on careful consideration of random factors and Monte-Carlo method,random kinematic parameters of this projectile and armored targets are obtained;then,scanning dependent zone theorem and deduction on space capture dependent zone are proved,so that capture probability models to aerial and ground targets are established,and the corresponding analytic formulas are developed;further,hit probability models on the armored targets are established,and corresponding hit probability analytic formulas of the EFP and the whole projectile are developed and solved respectively,so that the influence rules of random motion and structural geometries on the capture and hit probabilities are found.Those conclusions can guide structural design of the steady scanning platform and also lay some foundation for analyzing and evaluating the performance of the hedgehopping terminal sensitive projectiles. |
PDF Full Text Request