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Sullivan, John P.

Publications and source records attributed to Sullivan, John P..

12 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Global Skin-Friction Measurements Using Particle Image Surface FLow Visualization and a Luminescent Oil-Film

A quantitative global skin-friction measurement technique is proposed. An oil-film is doped with a luminescent molecule and thereby made to fluoresce in order to resolve oil-film thickness, and Particle Image Surface Flow Visualization is used to resolve the velocity field of the surface of the oil-film. Skin-friction is then calculated at location x as (x )xh, where x is the displacement of the surface of the oil-film and is the dynamic viscosity of the oil. The data collection procedure and data analysis procedures are explained, and preliminary experimental skin-friction results for flow over the wing of the CRM are presented.

FISF↗
NASA NTRS2012

Quantitative Global Heat Transfer in a Mach-6 Quiet Tunnel

This project developed quantitative methods for obtaining heat transfer from temperature sensitive paint (TSP) measurements in the Mach-6 quiet tunnel at Purdue, which is a Ludwieg tube with a downstream valve, moderately-short flow duration and low levels of heat transfer. Previous difficulties with inferring heat transfer from TSP in the Mach-6 quiet tunnel were traced to (1) the large transient heat transfer that occurs during the unusually long tunnel startup and shutdown, (2) the non-uniform thickness of the insulating coating, (3) inconsistencies and imperfections in the painting process and (4) the low levels of heat transfer observed on slender models at typical stagnation temperatures near 430K. Repeated measurements were conducted on 7 degree-half-angle sharp circular cones at zero angle of attack in order to evaluate the techniques, isolate the problems and identify solutions. An attempt at developing a two-color TSP method is also summarized.

Sullivan, John P.↗
NASA NTRS1999

Surface Measurement Techniques Temperature and Pressure Sensitive Paints

Luminescent molecular probes imbedded in a polymer binder form a temperature or pressure paint. On excitation by light of the proper wavelength, the luminescence,which is quenched either thermally or by oxygen, is detected by a camera or photodetector. From the detected luminescent intensity, temperature and pressure can be determined. Tl e basic photophysics, calibration, accuracy and the response of a luminescent paints is described followed by applications in wind tunnels and in rotating machinery.

Sullivan, John P.↗
NASA NTRS1998

Applications of Temperature and Pressure Sensitive Paints

Luminescent molecular probes imbedded in a polymer binder form a temperature or pressure paint. On excitation by light of the proper wavelength, the luminescence, which is quenched either thermally or by oxygen, is detected by a camera or photodetector. From the detected luminescent intensity, temperature and pressure can be determined. The basic photophysics, calibration, accuracy and time response of a luminescent paint is described followed by applications in low speed, transonic, supersonic and cryogenic wind tunnels and in rotating machinery.

Liu, Tian-Shu↗
NASA NTRS1996

Advanced Configurations for Very Large Subsonic Transport Airplanes

Recent aerospace industry interest in developing a subsonic commercial transport airplane with 50 percent greater passenger capacity than the largest existing aircraft in this category (the Boeing 747-400 with approximately 400-450 seats) has generated a range of proposals based largely on the configuration paradigm established nearly 50 years ago with the Boeing B-47 bomber. While this basic configuration paradigm has come to dominate subsonic commercial airplane development since the advent of the Boeing 707/Douglas DC-8 in the mid-1950's, its extrapolation to the size required to carry more than 600-700 passengers raises several questions. To explore these and a number of related issues, a team of Boeing, university, and NASA engineers was formed under the auspices of the NASA Advanced Concepts Program. The results of a Research Analysis focused on a large, unconventional transport airplane configuration for which Boeing has applied for a patent are the subject of this report. It should be noted here that this study has been conducted independently of the Boeing New Large Airplane (NLA) program, and with the exception of some generic analysis tools which may be common to this effort and the NLA (as will be described later), no explicit Boeing NLA data other than that published in the open literature has been used in the conduct of the study reported here.

McMasters, John H.↗
NASA NTRS1994

Wake measurements in a strong adverse pressure gradient

The behavior of wakes in adverse pressure gradients is critical to the performance of high-lift systems for transport aircraft. Wake deceleration is known to lead to sudden thickening and the onset of reversed flow; this 'wake bursting' phenomenon can occur while surface flows remain attached. Although 'wake bursting' is known to be important for high-lift systems, no detailed measurements of 'burst' wakes have ever been reported. Wake bursting has been successfully achieved in the wake of a flat plate as it decelerated in a two-dimensional diffuser, whose sidewalls were forced to remain attached by use of slot blowing. Pilot probe surveys, L.D.V. measurements, and flow visualization have been used to investigate the physics of this decelerated wake, through the onset of reversed flow.

Hoffenberg, R.↗
NASA NTRS1993

Two-, three-, and four-poster jets in cross flow

In connection with the problems of the ingestion of hot exhaust gases in engines of V/STOL and STOVL aircraft in ground effect, a series of studies have been undertaken. Ground impinging, two- and three-poster jets operating in the presence of cross flow were studied. The current paper is divided into two parts. The first part is a comparison of the low speed, two-, three-, and four-poster jet cases, with respect to the flowfield in the region of interaction between the forward and the jet flows. These include cases with mass balanced inlet suction. An analysis of the inlet entry plane of the low speed two- and three-poster jet cases is also given. In the second part, high speed results for a two jet configuration without inlet suction are given. The results are based on quantitative, marker concentration distributions obtained by digitizing video images.

Vukits, Thomas J.↗
NASA NTRS1991

Experimental results of a propeller/wing interaction study

Steady state measurements have been performed on a propellar and a wing in a tractor configuration, to investigate the consequences of mutual interference on overall performance. For certain geometries wing lift is found to be enhanced, and wing drag to be decreased. The unsteady nature of the propeller-wing aerodynamic interaction has been studied using flow visualization. Results obtained indicate that the tip vortex is severed at the wing leading edge, the severed tip vortex filaments shear in a spanwise direction relative to one another, and these displaced filaments deform to reconnect at the trailing edge.

Johnson, Robert T.↗
NASA NTRS1990

Propeller tip vortex interactions

Propeller wakes interacting with aircraft aerodynamic surfaces are a source of noise and vibration. For this reason, flow visualization work on the motion of the helical tip vortex over a wing and through the second stage of a counterrotation propeller (CRP) has been pursued. Initially, work was done on the motion of a propeller helix as it passes over the center of a 9.0 aspect ratio wing. The propeller tip vortex experiences significant spanwise displacements when passing across a lifting wing. A stationary propeller blade or stator was installed behind the rotating propeller to model the blade vortex interaction in a CRP. The resulting vortex interaction was found to depend on the relative vortex strengths and vortex sign.

Johnston, Robert T.↗
NASA NTRS1989

Propeller/wing interaction

The present experimental investigation of the steady-state and unsteady-state effects due to the interaction between a tractor propeller's wake and a wing employs, in the steady case, wind tunnel measurements at low subsonic speed; results are obtained which demonstrate wing performance response to variations in configuration geometry. Other steady-state results involve the propeller-hub lift and side-force due to the wing's influence on the propeller. The unsteady effects of interaction were studied through flow visualization of propeller-tip vortex distortion over a wing, again using a tractor-propeller configuration.

Witkowski, David P.↗
NASA NTRS1988

Aerodynamic interaction between propellers and wings

A combined computational/experimental investigation has been conducted to determine the time-averaged interactive performance of a propeller and wing in tractor configuration at Mach 0.1 and Re=470,000, based on a wind tunnel model wing chord of 8 in. Wing angle-of-attack was varied from 0 to +13 deg, and propeller advance ratio ranged from 2.4 (windmilling) to 1.1 (maximum power). Both a semiempirical model and a vortex lattice simulation were used in the computational analysis. Good agreement has been obtained between theory and experiment.

Witkowski, David↗