Measurements are reported on the characteristics of the vortex wakes that trail from 0.03-scale models of a B-747 and a DC-10. Included are the downwash distributions obtained with a hot-film anemometer probe for the standard landing configurations, and the rolling moments induced on various following wings by the vortex wakes of several configurations of both wake-generating models. Both sets of data are presented for downstream distances of 81 and 162 ft, i.e., scale distances of 0.5 and 1.0 mile.frequency, Hz L = lift, Ib M = rolling moment, ft -Ib q = dynamic pressure, pUi/2, lb/ft 2 r = radius, ft S = wing planform area, ft 2 £/oo = freestream velocity, ft/s w, v, w = velocity components in x, y, and z directions, ft/s x = distance in flight direction, ft y = distance in spanwise direction, ft z = distance in vertical direction, ft a = angle of attack, deg j8 = yaw angle, deg F = bound circulation, ft 2 /s p = air density, slugs/ft 3 Subscripts av = averaged over time at a given point / = following model g = wake-generating model max = maximum on one side of centerline mi = minimum at a given point mx = maximum at a given point p = pitch r = roll
The National Aeronautics and Space Administration's (NASA) Airspace Systems Program is contributing air traffic management research in support of the 2025 Next Generation Air Transportation System (NextGen). Contributions support research and development needs provided by the interagency Joint Planning and Development Office (JPDO). These needs generally call for integrated technical solutions that improve systemlevel performance and work effectively across multiple domains and planning time horizons. In response, the Airspace Systems Program is pursuing an integrated research approach and has adapted systems engineering best practices for application in a research environment. Systems engineering methods aim to enable researchers to methodically compare different technical approaches, consider system-level performance, and develop compatible solutions. Systems engineering activities are performed iteratively as the research matures. Products of this approach include a demand and needs analysis, system-level descriptions focusing on NASA research contributions, system assessment and design studies, and common systemlevel metrics, scenarios, and assumptions. Results from the first systems engineering iteration include a preliminary demand and needs analysis; a functional modeling tool; and initial system-level metrics, scenario characteristics, and assumptions. Demand and needs analysis results suggest that several advanced concepts can mitigate demand/capacity imbalances for NextGen, but fall short of enabling three-times current-day capacity at the nation's busiest airports and airspace. Current activities are focusing on standardizing metrics, scenarios, and assumptions, conducting system-level performance assessments of integrated research solutions, and exploring key system design interfaces.
This paper details the extensive effort required to achieve uniform flow from the AMELIA wind tunnel model's circulation control wings. Performed in September of 2011 in the Fluid Mechanics Lab at NASA Ames Research Center, the calibration required a 500hp instrument-quality air compressor capable of delivering 250 CFM at pressures greater than 70 psi. It was found that the geometery within AMELIA's circulation control supply plenums produced highly vortical flow, resulting in poor circulation control performance as measured by traversing external and stationary internal total pressure probes, as well as surface oil flow. Adjustments were made within AMELIA to the supply conditions of each plenum including internal butterfly valve position, model inlet pressure, and total volume flow rate delivered to the model. Each plenum was further modified with a treatment of metal foam and various other materials including perforated plates, metal barriers, and Rigimesh material. The combination of metal foam and densly woven Rigimesh resulted in uniform spanwise flow at acceptable plenum pressures.
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