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Igoe, W. B.

Publications and source records attributed to Igoe, W. B..

15 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

National transonic facility shakedown test results and calibration plans

The results of the shakedown tests and the calibration plan of the National Transonic Facility (NTF) are presented. The facility is designed to operate in both air and nitrogen modes, cover Mach numbers from 0.2 to 1.2, pressures up to 8.8 atm and temperatures between 77 and 339 K. The facility data system is built around four 16-bit minicomputers with a total memory of three megabytes. A portable cryogenic chamber is available. The tunnel systems were operated in a series of tests in Mach number range of 0.2 to 1.17, pressures up to 8.5 atm, and temperatures down to 100 K. The calibration plan includes steady-state and dynamic calibration, as well as wall interference studies. The facility underwent the checkout of the model attitude, plenum isolation, and model access systems, followed by aerodynamic calibration in 1984. Schematic drawings and diagrams are included.

Bruce, W. E., Jr.↗
NASA NTRS1981

Description of 0.186-scale model of high-speed duct of national transonic facility

The National Transonic Facility (NTF) is a pressurized cryogenic wind tunnel with a 2.5 m square test section. A 0.186-scale model of the NTF was used to simulate the aerodynamic performance of the components of the high-speed duct of the NTF. These components consist of a wide-angle diffuser, settling chamber, contraction section, test section, model support section, and high-speed diffuser. The geometry of the model tunnel, referred to as the diffuser flow apparatus is described, and some of its operating characteristics are presented.

Gentry, C. L., Jr.↗
NASA NTRS1980

Characteristics and status of the US National Transonic Facility

A major application of the cryogenic wind tunnel concept is discussed. A closed return fan driven circuit with a 2.5 meter square slotted test section, pressurized up to 8.85 atmospheres, and providing chord Reynolds numbers of 120 million based on a chord of 0.25 meter at transonic speeds using cold nitrogen as the test gas is described.

Igoe, W. B.↗
NASA NTRS1979

Aerodynamic characteristics at low Reynolds numbers of several heat-exchanger configurations for wind-tunnel use

In response to design requirements of the National Transonic Facility, aerodynamic tests were conducted to determine the pressure-drop, flow-uniformity, and turbulence characteristics of various heat-exchanger configurations as a function of Reynolds number. Data were obtained in air with an indraft flow apparatus operated at ambient temperature and pressure. The unit Reynolds number of the tests varied from about 0.06 x 10 to 6th power to about 1.3 x 10 to 6th power per meter. The test models were designed to represent segments of full-scale tube bundles and included bundles of round tubes with plate fins in both staggered and inline tube arrays, round tubes with spiral fins, elliptical tubes with plate fins, and an inline grouping of tubes with segmented fins.

Johnson, W. G., Jr.↗
NASA NTRS1979

Full-scale aircraft simulation with cryogenic tunnels and status of the National Transonic Facility

The effect of thermal and caloric imperfections in cryogenic nitrogen on boundary layers was determined to indicate that in order to simulate nonadiabatic laminar or turbulent boundary layers in a cryogenic nitrogen wind tunnel, the flight enthalpy ratio, rather than the temperature ratio, should be reproduced. The absence of significant real gas effects on both viscous and inviscid flows makes it unlikely that there will be large real gas effects on the cryogenic tunnel simulation of shock boundary layer interactions or other complex flow conditions encountered in flight. Condensation effects were studied to determine the minimum usable temperature and indicated that under most circumstances free stream Mach number rather than maximum local Mach number determines the onset of condensation effects.

Kilgore, R. A.↗
NASA NTRS1979

Full scale aircraft simulation with cryogenic tunnels and status of the National Transonic Facility

The paper reviews the results of some of the real-gas studies made at Langley that are directly related to establishing the range of operating conditions that can be used in a cryogenic nitrogen wind tunnel and still be assured of valid full-scale simulation. Consideration is given to the important aerodynamic features, anticipated performance capability, status of construction, and projected operating data for the National Transonic Facility.

Kilgore, R. A.↗
NASA NTRS1974

Calibration of the Langley 16-foot transonic tunnel with test section air removal

The Langley 16-foot transonic tunnel with test section air removal (plenum suction) was calibrated to a Mach number of 1.3. The results of the calibration, including the effects of slot shape modifications, test section wall divergence, and water vapor condensation, are presented. A complete description of the wind tunnel and its auxiliary equipment is included.

Corson, B. W., Jr.↗