Accession Number : ADA262507


Title :   Anti-Tank Spike-Nosed Projectiles With Vortex Rings: Steady and Non- Steady Flow Simulations


Descriptive Note : Final rept. Jan 90-Jan 91


Corporate Author : ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD


Personal Author(s) : Mikhail, Ameer G


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a262507.pdf


Report Date : Mar 1993


Pagination or Media Count : 55


Abstract : Numerical computations are reported for a spike-nosed projectile configuration with a vortex generator ring. A new vortex-dominated flow field is computed at supersonic speeds of M - 3.5, 3.0, and 1.9. A time-dependent Navier- Stokes computational technique with a zonal gridding was used. The axial force at zero angle of attack was computed and found to be in good agreement with the wind tunnel data at Mach 3.0. The sting quantitative effect on the axial force coefficient and the flow pattern was found to be very minor for the present case at Mach 3.5. A high drag solution for a case computed at Mach 3.5 was obtained by imposing a cross flow velocity of seven percent of the freestream velocity. This result removed any doubt that the wind tunnel results for that Mach number were for the high drag mode. An additional interesting case was computed at Mach 1.9; and the flow was found to be of the oscillator (buzzing) type. The frequency of the oscillation was computed as 5333 Hz and indicated that the designers of the projectile in 1980 were apparently not aware of the possible buzzing flow along the projectile trajectory when it decelerates from Mach 3.5 to 1.9. They had tested the projectile only at Mach 3.5 and 3.0. No tests were made at Mach 1.9 or lower.... Anti-tank projectiles, Spikes, Aerodynamic drag, Supersonic drag, Numerical integration, Axisymmetric flow, Turbulent flow, Flow field, Unsteady flow.


Descriptors :   *PROJECTILES , *ANTITANK AMMUNITION , TEST AND EVALUATION , VELOCITY , FREQUENCY , OSCILLATORS , COMPUTATIONS , TURBULENT FLOW , ANGLE OF ATTACK , TUNNELS , TIME , FLOW FIELDS , INTEGRATION , COEFFICIENTS , NUMERICAL INTEGRATION , CONFIGURATIONS , AERODYNAMIC DRAG , AXISYMMETRIC , PATTERNS , MACH NUMBER , AGREEMENTS , UNSTEADY FLOW , GENERATORS , RINGS , OSCILLATION , TRAJECTORIES , PROJECTILE TRAJECTORIES , AERODYNAMICS , VORTEX GENERATORS , SPIKES , CROSS FLOW , AXISYMMETRIC FLOW , SUPERSONIC DRAG


Subject Categories : Ammunition and Explosives
      Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE