23,900 research outputs found
Laser-velocimeter flow-field measurements of an advanced turboprop
Non-intrusive measurements of velocity about a spinner-propeller-nacelle configuration at a Mach number of 0.8 were performed. A laser velocimeter, specifically developed for these measurements in the NASA Lewis 8-foot by 6-foot Supersonic Wind Tunnel, was used to measure the flow-field of the advanced swept SR-3 turboprop. The laser velocimeter uses an argon ion laser and a 2-color optics system to allow simultaneous measurements of 2-components of velocity. The axisymmetric nature of the propeller-nacelle flow-field permits two separate 2 dimensonal measurements to be combined into 3 dimensional velocity data. Presented are data ahead of and behind the prop blades and also a limited set in between the blades. Aspects of the observed flow-field such as the tip vortex are discussed
Bose-Einstein Correlations and the Equation of State of Nuclear Matter
Within a relativistic hydrodynamic framework, we use four different equations
of state of nuclear matter to compare to experimental spectra from CERN/SPS
experiments NA44 and NA49. Freeze-out hypersurfaces and Bose-Einstein
correlation functions for identical pion pairs are discussed. We find that
two-pion Bose-Einstein interferometry measures the relationship between the
temperature and the energy density in the equation of state during the late
hadronic stage of the fireball expansion. Little sensitivity of the
light-hadron data to a quark-gluon plasma phase-transition is seen.Comment: 4 pages, including 4 figures. You can also download a PostScript file
of the manuscript from http://p2hp2.lanl.gov/people/schlei/eprint.htm
The need for a new measure of contaminant cloud concentration reduction
In this paper it will be demonstrated that conventional measures used to characterize contaminant concentration reduction are impractical and inadequate to describe the important case of a contaminant cloud. A new measure, the expectedmass-fraction function, is developed and shown to have desirable experimental and theoretical features. Some contaminant plume data is used to illustrate the application of this new measure
Aerothermal modeling program. Phase 2, element B: Flow interaction experiment
NASA has instituted an extensive effort to improve the design process and data base for the hot section components of gas turbine engines. The purpose of element B is to establish a benchmark quality data set that consists of measurements of the interaction of circular jets with swirling flow. Such flows are typical of those that occur in the primary zone of modern annular combustion liners. Extensive computations of the swirling flows are to be compared with the measurements for the purpose of assessing the accuracy of current physical models used to predict such flows
Energy efficient engine. Fan and quarter-stage component performance report
The fan configuration for the general Electric/NASA Energy Efficient Engine was selected following an extensive preliminary design study. The fan has an inlet radius ratio of 0.342 and a specific flowrate of 208.9 Kg/sec/sq. m (42.8 1bm/sec/sq. ft). The design corrected tip speed is 411.5 m/sec (1350 ft/sec) producing a bypass flow total-pressure ratio of 1.65 and a core flow total-pressure ratio of 1.6. The design bypass ratio is 6.8. The aerodynamic design point corresponds to the maximum climb power setting at Mach 0.8 and 10.67 Km (35,000 ft) altitude. The fully-instrumented fan component was tested in the Lynn Large Fan Test Facility in 1981. The overall performance results, reported herein, showed excellent fan performance with the fan meeting all of its component test goals of flow, efficiency and stall margin
Wind turbine generator rotor blade concepts with low cost potential
Four processed for producing blades are examined. Two use filament winding techniques and two involve filling a mold or form to produce all or part of a blade. The processes are described and a comparison is made of cost, material properties, design and free vibration characteristics. Conclusions are made regarding the feasibility of each process to produce low cost, structurally adequate blades
ΠΠ°ΠΌΡΡΠΈ ΠΠ°Π΄ΠΈΠΌΠ° ΠΡΠΈΠ³ΠΎΡΡΠ΅Π²ΠΈΡΠ° ΠΠ°Π½ΠΆΠ΅Π»ΠΈΡ (1933β2013)
21 Π°Π²Π³ΡΡΡΠ° 2013 Π³ΠΎΠ΄Π° ΡΡΠ΅Π» ΠΈΠ· ΠΆΠΈΠ·Π½ΠΈ Π°ΠΊΠ°Π΄Π΅ΠΌΠΈΠΊ ΠΠ°ΡΠΈΠΎΠ½Π°Π»ΡΠ½ΠΎΠΉ Π°ΠΊΠ°Π΄Π΅ΠΌΠΈΠΈ Π½Π°ΡΠΊ Π£ΠΊΡΠ°ΠΈΠ½Ρ, ΠΏΡΠΎΡΠ΅ΡΡΠΎΡ, Π΄ΠΎΠΊΡΠΎΡ ΡΠΈΠ·ΠΈΠΊΠΎ-ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΡ
Π½Π°ΡΠΊ, Π³Π»Π°Π²Π½ΡΠΉ Π½Π°ΡΡΠ½ΡΠΉ ΡΠΎΡΡΡΠ΄Π½ΠΈΠΊ Π€ΠΈΠ·ΠΈΠΊΠΎ-ΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΈΠ½ΡΡΠΈΡΡΡΠ° Π½ΠΈΠ·ΠΊΠΈΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡ ΠΈΠΌ. Π.Π. ΠΠ΅ΡΠΊΠΈΠ½Π° ΠΠΠ Π£ΠΊΡΠ°ΠΈΠ½Ρ, Π·Π°ΡΠ»ΡΠΆΠ΅Π½Π½ΡΠΉ Π΄Π΅ΡΡΠ΅Π»Ρ Π½Π°ΡΠΊΠΈ ΠΈ ΡΠ΅Ρ
Π½ΠΈΠΊΠΈ Π£ΠΊΡΠ°ΠΈΠ½Ρ ΠΠ°Π΄ΠΈΠΌ ΠΡΠΈΠ³ΠΎΡΡΠ΅Π²ΠΈΡ ΠΠ°Π½ΠΆΠ΅Π»ΠΈΠΉ
Aerothermal modeling program, phase 2
The main objectives of the Aerothermal Modeling Program, Phase 2 are: to develop an improved numerical scheme for incorporation in a 3-D combustor flow model; to conduct a benchmark quality experiment to study the interaction of a primary jet with a confined swirling crossflow and to assess current and advanced turbulence and scalar transport models; and to conduct experimental evaluation of the air swirler interaction with fuel injectors, assessments of current two-phase models, and verification the improved spray evaporation/dispersion models
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