69 research outputs found
An experimental study of transonic flow about a supercritical airfoil. Static pressure and drag data obtained from tests of a supercritical airfoil and an NACA 0012 airfoil at transonic speeds, supplement
Surface static-pressure and drag data obtained from tests of two slightly modified versions of the original NASA Whitcomb airfoil and a model of the NACA 0012 airfoil section are presented. Data for the supercritical airfoil were obtained for a free-stream Mach number range of 0.5 to 0.9, and a chord Reynolds number range of 2 x 10 to the 6th power to 4 x 10 to the 6th power. The NACA 0012 airfoil was tested at a constant chord Reynolds number of 2 x 10 to the 6th power and a free-stream Mach number range of 0.6 to 0.8
Detailed transonic flow field measurements about a supercritical airfoil section
The transonic flow field about a Whitcomb-type supercritical airfoil profile was measured in detail. In addition to the usual surface pressure distributions and wake surveys, schlieren photographs were taken and velocity vector profiles were determined in the upper surface boundary layer and in the near wake. Spanwise variations in the measured pressures were also determined. The data are analyzed with the aid of an inviscid transonic finite-difference computer program as well as with boundary layer modeling and calculation schemes
An experimental study of transonic flow about a supercritical airfoil
A series of experiments was conducted on flow fields about two airfoil models whose sections are slight modifications of the original Whitcomb supercritical airfoil section. Data obtained include surface static-pressure distributions, far-wake surveys, oil-flow photographs, pitot-pressure surveys in the viscous regions, and holographic interferograms. These data were obtained for different combinations of lift coefficient and free-stream Mach number, which included both subcritical cases and flows with upper-surface shock waves. The availability of both pitot-pressure data and density data from interferograms allowed determination of flow-field properties in the vicinity of the trailing edge and in the wake without recourse to any assumptions about the local static pressure. The data show that significant static-pressure gradients normal to viscous layers exist in this region, and that they persist to approximately 10% chord downstream of the trailing edge. Comparisons are made between measured boundary-layer properties and results from boundary-layer computations that employed measured static-pressure distributions, as well as comparisons between data and results of airfoil flow-field computations
A study of secondary injection of gases into a supersonic flow
Secondary injection of gases into supersonic flo
ARTIST???S CREATIVE CONTRIBUTIONS IN THE CONTEXT OF INTERDISCIPLINARY RESEARCH
While expectations regarding art???s potential contributions to the interdisciplinary research context continue to grow, the creative endeavors of individual artists remain under-examined, perhaps because of the inter-relational nature of joint research settings. To explore, how artists navigate their contribution to a given research community, this study reviews the art practice of Seung-Hyun Ko, who participated in Science Walden, a Convergent Research Center carrying out an interdis-ciplinary research project that aimed to build an ecologically sustainable community. Drawing on comprehensive views of creativity that emphasize the importance of the social context in which the efforts of individuals emerge and are assessed, the study examines Ko???s recent collaborative practice in Science Walden within the larger context of his long-term practice as a leading artist of Yatoo, a bioregionally conscious artist community. Ko???s responses to the opportunities and challenges of his involvement in these two interrelated contexts disclose the value of the creative dynamics of interdisciplinary research, with implications for the increasingly diverse interdisciplinary research practices emerging within science and technology
A Study of the Interaction of Gaseous Jets from Transverse Slots with Supersonic External Flows
The paper describes a study concerning the sonic injection of a gaseous jet through a transverse slot nozzle in a wall into an external flow which is uniform outside of a turbulent boundary layer. An analytic model of the flowfield has been constructed in which conservation of
momentum is applied to a control volume at the jet nozzle exit. A series of flat-plate experiments was conducted with normal, sonic jets at external flow Mach numbers of 2.61, 3.50, and 4.54. Pressure data near separation and the plateau were in agreement with existing correlations. Comparisons of the trends predicted by the analysis with two-dimensional force data from these experiments and from other sources showed good agreement. Values
of amplification factor, the upstream interaction force plus the jet thrust divided by the vacuum thrust of a sonic jet, of 2.9 to 3.2 were measured. The amplification factor is relatively insensitive to variations in external flow Mach number and variations in injectant gas properties. A correlation of data obtained from experiments with finite-span slots demonstrates that the effective jet penetration height and the slot span are the important characteristic
dimensions of such flowfields
Hypersonic Nozzle-Afterbody Experiment - Flow visualization and boundary-layer measurements
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