Short Takeoff Performance using Circulation Control

Historically, powered lift takeoff analysis has been prohibitively expensive for use in preliminary design. For powered lift, the coupling of aircraft systems invalidates traditional simplistic methods often used in early aircraft sizing. This research creates a tool that will automate the process of takeoff and balanced field length calculations for a circulation control wing aircraft. The process will use high fidelity techniques, such as computational fluid dynamics in order to capture the coupled effects present in circulation control along with Gaussian processes to create a metamodel of that same data to be implemented in a modular takeoff/BFL model. The model was used to examine the performance of a STOL transport and it showed an optimal flap deflection of 64 ̊ and diminishing returns on mass flow rates exceeding 12 kg/s. Additional analysis of the STOL transport showed that delaying either the mass flow or the flap deflection until later in the ground roll reduced the balanced field length by up to 8%. In the process of creating the takeoff code, additional consideration was put into the determination of the rotation velocity. It was found that a relationship between lift to weight better defined the rotation velocity with the circulation control model and was found to be within about 10% of traditional techniques.