The aerodynamic characteristics of nine configurations of supersonic continuous deflectable nose guided missiles have been investi-gated. Then the optimized geometry is achieved based on the accuracy of confliction with constant target in ground to ground mission. The studied configurations consists of a spherical nose tip, a tangent ogive, one set of stabilizing tail fines and a cylindrical body that its mid-section is flexible to form an arc of a circle. So the cylindrical body consists of a fix part in vicinity of nose, middle flexible part and main body with stabilizers. The effects of fix length (Fix=0, 1.5, 3Cal) and flexible length (Flex=1, 2.5, 5Cal) parameters on the aerodynamics and flight dynamics of guided missile have been studied. A code has been developed to solve full Navier-Stokes equations using finite volume and Runge-Kutta time stepping techniques and modified Baldwin-Lomax turbulence model. Multi-block technique is also used to solve main body and fin parts flow fields. Further, a 3 degree of freedom code along with a pure pursuit guidance subroutine has been developed to compare planar flight dynamics of missiles. It is found that although the missiles with bigger lengths for fix and flex parts show more maneuverability, but this is not favorable for all missile missions as sometimes it decreases the confliction accuracy. Flight dynamic analysis shows that a change in initial launch angle may shift the favorite configuration. This means only the aerodynamic defined aim functions cannot completely supersede flight dynamic analysis in geometric optimization. Further, the thrust vector moment is an important portion of total control moment as it enhances the hitting accuracy and also decreases the importance of geometry.

Keywords