On the Use of Miniature Actuator Bumps (MABs) for Nozzle Thrust Vectoring

Abstract : Experimental and Computational studies are conducted to investigate the use of miniature actuator bumps (MABs) for nozzle jet vectoring. The control concept features asymmetric deployment of MABs around the nozzle throat to subsonically skew the sonic plane and shift the throat for jet vectoring. Cold-flow jet studies are conducted to investigate the effects of actuator parameters (deployment height, location, and shape) on pitch vector control for axisymmetric and non-axisymmetric nozzles. Experiments are conducted in a Jet Facility at the University of Toledo and CFD simulations are conducted using a full, 3-D Navier-Stokes flow solver on select nozzle geometries. Measurements indicate that the thrust vector control can be achieved with small actuator deployment heights, and that the sensitivity is increased when the actuator is used near the nozzle throat. Also, MAB control is more effective for two-dimensional nozzles -- a result that is consistent with earlier studies conducted using fluidic actuators. The underlying mechanism of subsonic flow turning holds for a range of stagnation pressure and throat conditions. Thrust vectoring using the MAB concept offers distinct advantages over traditional control approaches by way of reducing the weight and cost of the control actuation system through proper design and integration of microelectromechanical systems (MEMS) actuation device for MAB deployment.