Calculation On Linear And Nonlinear Aerodynamic Characteristics Of Projectile

Aerodynamic design is very important in the designation of modern weapons, current and future weapons are designed to transiently fly at very high angles of attack and require highly maneuverability. So it is very important to predict the aerodynamics of weapons accurately in the designation of modern weapons and their control systems. In this paper, the aerodynamic characteristics at small angle of attack and large angle of attack for cartridge and rocket was calculated and analyzed. Additionally, the software that use for the calculation of aerodynamic characteristics was designed.First, the method of prediction of aerodynamic characteristics at small angle of attack was introduced. The paper studies the method of prediction of aerodynamic characteristics of slender body and wings. And the method of prediction of aerodynamic characteristics at small angle of attack of whole projectile was given in the paper.Second, the method of prediction of aerodynamic characteristics at large angle of attack by using of the cross-flow theory and equivalent angle of attack theory was introduced. In the large Angle of attack flight, aerodynamic characteristics show nonlinear characteristics. The thesis given the method of prediction of nonlinear aerodynamic characteristics at large angle of attack, and it provides a basis for pneumatic shape design.Third, the software that uses for prediction of aerodynamic characteristics of projectile was developed in this paper. On the basis of analysis on source code of the data compendium (Missile Datcom) software, the software was developed in combination with development achievement. A friendly graphical user interface was programmed by means of VC++、Fortran and VB software.Finally, the software code was verified by the wind tunnel experiment data of projectile. The results show that the software can provide accurate estimation for projectile aerodynamic force coefficient within the certain and find application for different projectile configuration. And the factors that can influence results were analyzed, in order to improve the precision of the calculation.