Modern technologies coupled with advanced research have allowed model predictive control (MPC) to be applied to new and often experimental systems. The purpose of this research is to develop a model predictive control algorithm for tip-jet reaction drive system. This system's faster dynamics require an extremely short sampling rate, on the order of 20ms, and its slower dynamics require a longer prediction horizon. This coupled with the fact that the tip-jet reaction drive system has multiple control inputs makes the integration of an online MPC algorithm challenging. In order to apply a model predictive control to the system in question, an algorithm is proposed that combines multiplexed inputs and a feasible cooperative MPC algorithm. In the proposed algorithm, it is hypothesized that the computational burden will be reduced from approximately Hp(Nu + Nx)3 to pHp(Nx+1)3 while maintaining control performance similar to that of a centralized MPC algorithm. To capture the performance capability of the proposed controller, a comparison its performance to that of a multivariable proportional-integral (PI) controller and a centralized MPC is executed. The sensitivity of the proposed MPC to various design variables is also explored. In terms of bandwidth, interactions, and disturbance rejection, the proposed MPC was very similar to that of a centralized MPC or PI controller. Additionally in regards to sensitivity to modeling error, there is not a noticeable difference between the two MPC controllers. Although the constraints are handled adequately for the proposed controller, adjustments can be made in the design and sizing process to improve the constraint handling, so that it is more comparable to that of the centralized MPC. Given these observations, the hypothesis of the dissertation has been confirmed. The proposed MPC does in fact reduce computational burden while maintaining close to centralized MPC performance.

The application of an ejector nozzle integrated with a reaction drive rotor configuration for a vertical takeoff and landing rotorcraft is considered in this research. The ejector nozzle is a device that imparts energy from a high speed airflow source to a lower speed secondary airflow inside a duct. The overall nozzle exhaust mass flow rate is increased through fluid entrainment, while the exhaust gas velocity is simultaneously decreased. The exhaust gas velocity is strongly correlated to the jet noise produced by the nozzle, making the ejector a good candidate for propulsion system noise reduction. Ejector nozzles are mechanically simple in that there are no moving parts. However, coupled fluid dynamic processes are involved, complicating analysis and design. Geometric definitions of the ejector nozzle are determined through a reduced fidelity, multi-disciplinary, representation of the rotary wing ejector. The resulting rotary wing ejector geometric sizing procedure relates standard vehicle and rotor design parameters to the ejector. Additionally, a rotary wing ejector performance procedure is developed to compare this rotor configuration to a conventional rotor. Performance characteristics and aerodynamic effects of the rotor and ejector nozzle are analytically studied. Ejector nozzle performance, in terms of exit velocities, is compared to the primary reaction drive nozzle; giving an indication of the potential for noise reduction. Computational fluid dynamics are paramount in predicting the aerodynamic effects of the ejector nozzle located at the rotor blade tip. Two-dimensional, steady-state, Reynolds-averaged Navier-Stokes (RANS) models are implemented for sectional lift and drag predictions required for the rotor aerodynamic model associated with both the rotary wing ejector sizing and performance procedures. A three-dimensional, unsteady, RANS simulation of the rotary wing ejector is performed to study the aerodynamic interactions between the ejector nozzle and rotor. Overall performance comparisons are made between the two- and three-dimensional models of the rotary wing ejector, and a similar conventional rotor.