Numerical Investigation of the Effect of Lattice Fin on the AerodynamicForces of a Missile

In the present study, using numerical solution to predict the flow field and aerodynamic forces of three types of missile with the different designs of the fin and also to comparison of the ordinary and lattice fin. One of the most important parameters in the stability and performance of a missile is the fins. The design and optimization of these fins can have significant effects on the aerodynamic efficiency and maneuverability of the missile. The results are presented in the range of Mach numbers 0.5 to 3 and the angle of attack 0 to 10 degrees. In this study, parameters such as drag force, lift force, flow field, and Mach number distribution were analyzed. The results showed that missile with lattice fin in the tail position; it produced the greatest drag force. Also, the lift force for the missile with lattice fin in the tail position is higher than the other two missiles (ordinary and lattice canard) and increases with increasing angle of attack. The momentum forces for fins located in the canard position shows less value for the lattice fin than the flat fin. The results show that the drag force also increased from subsonic Mach numbers to supersonic Mach numbers, and then decreased with rising Mach numbers. In addition, with the increase of Mach number to the hypersonic Mach numbers, normal shock waves are formed in front of the fin, causing a sharp increase in drag force.