CFD Simulations of a Finned Projectile with Microflaps for Flow Control

Abstract EN

This research describes a computational study undertaken to determine the effect of a flow control mechanism and its associated aerodynamics for a finned projectile.

The flow control system consists of small microflaps located between the rear fins of the projectile.

These small microflaps alter the flow field in the aft finned region of the projectile, create asymmetric pressure distributions, and thus produce aerodynamic control forces and moments.

A number of different geometric parameters, microflap locations, and the number of microflaps were varied in an attempt to maximize the control authority generated by the flaps.

Steady-state Navier-Stokes computations were performed to obtain the control aerodynamic forces and moments associated with the microflaps.

These results were used to optimize the control authority at a supersonic speed, M=2.5.

Computed results showed not only the microflaps to be effective at this speed, but also configurations with 6 and 8 microflaps were found to generate 25%–50% more control force than a baseline 4-flap configuration.

These results led to a new optimized 8-flap configuration that was further investigated for a range of Mach numbers from M=0.8 to 5.0 and was found to be a viable configuration effective in providing control at all of these speeds.