Available at: https://digitalcommons.calpoly.edu/theses/1153
Date of Award
MS in Aerospace Engineering
The circulation control system onboard Cal Poly's Advanced Model for Extreme Lift and Improved Aeroacoustics was a critical component of a highly complex wind tunnel model produced in order to fulfill the requirements of a NASA Research Announcement awarded to David Marshall of the Aerospace Engineering Department. The model was based on a next generation, 150 passenger, regional, cruise efficient, short take-off and landing concept aircraft that achieved high lift through circulation control wings and over-the-wing mounted engines. The wind tunnel model was 10-ft in span, used turbine propulsion simulators, and had a functioning circulation control system driven from tunnel supplied high pressure air. Wind tunnel test results will be compiled into an open-source database intended for validation of predictive tools whose purpose is to advance the state- of-the-art in predictive capabilities for the next generation aircraft configurations.
The model's circulation control system produced highly directional, nonuniform flow, and required significant modification in order to generate flow suitable for representation in predictive software. The effort and methods used to generate uniform flow along the circulation control slots is detailed herein. Additionally the results of the system characterization are presented and include a thorough analysis of the slot height, the wing symmetry, and total pressure at the circulation control jet exit. These datasets are intended to aid in making adjustments to the simulation such that it accurately reflects the condition at which the model was tested.
Many flow visualization results from the wind tunnel test are also presented to serve as a medium of comparison for results from predictive tools. Oil flow visualization was conducted at many test conditions and provides insight to AMELIA's surface flow in blown and unblown regions. Of particular interest were streamlines at the wingblend, which exhibited some outboard turning, and streamlines on the lower surface where the leading edge stagnation point was investigated. Smoke flow visualization was also utilized to explore the flowfield. The deflection of a individual streamline, under the influence of a changing discharge coefficient as investigated along with the discharge coefficients effect on the extended flowfield. Collectively, the images depict the massive augmentation of the flowfield caused by the presence of the circulation control wing.