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Results for “ASPECT RATIO”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

Performance of a high-work, low-aspect-ratio turbine stator tested with a realistic inlet radial temperature gradient

A 0.767-scale model of a turbine stator designed for the core of a high-bypass-ratio aircraft engine was tested with uniform inlet conditions and with an inlet radial temperature profile simulating engine conditions. The principal measurements were radial and circumferential surveys of stator-exit total temperature, total pressure, and flow angle. The stator-exit flow field was also computed by using a three-dimensional Navier-Stokes solver. Other than temperature, there were no apparent differences in performance due to the inlet conditions. The computed results compared quite well with the experimental results.

Stabe, Roy G.↗
NASA NTRS1991

Stress intensity factors for large aspect ratio surface and corner cracks at a semi-circular notch in a tension specimen

Stress intensity factor solutions for semielliptic surface and quarter-elliptic corner cracks emanating from a semicircular notch in a tension specimen are presented. A three-dimensional finite-element analysis in conjunction with the equivalent domain integral was used to calculate stress intensity factors (SIF). SIF solutions for surface or corner crack (crack length to depth ratio of 2) at a notch are presented for a wide range of crack sizes and notch radii. Results showed that the SIF are larger for larger crack lengths and for larger notch radii. The SIF are nearly constant all along the crack front for deep surface cracks and for all corner cracks analysed.

Shivakumar, K. N.↗
NASA NTRS1991

Comparison of cryogenic wind tunnel, flight, and computational results for a thin, low-aspect-ratio wing

A research program was conducted at NASA Langley Research Center to build and test a thin, pressure instrumented wing. The wing chosen was the canard of the X-29, which has a maximum thickness of 5 percent of chord. The wing has 90 pressure taps and was built utilizing an advanced laminated metal technique. It was tested in the 0.3-Meter Transonic Cryogenic Tunnel at transonic Mach numbers and over a wide range of Reynolds number. The data are compared with flight data and Navier-Stokes computational results.

Lawing, Pierce L.↗
NASA NTRS1991

A study of flow separation on an aspect ratio three flap at Mach number 2.4

Static pressure distributions and dark central ground interferometry are used to document the flow on a flap over a range of Reynolds numbers and deflection angles. The pressure profiles and interferograms are analyzed to distinguish laminar, transitional and turbulent flows in attached, incipient and separated cases. Sideplates are used to compare two and three dimensional effects. Data is also presented for extended flaps used to isolate the effect of the trailing edge expansion. The issues of unsteadiness and hysteresis are also addressed.

Coon, Michael D.↗
NASA NTRS1992

High-Aspect-Ratio Rotating Cell-Culture Vessel

Cylindrical rotating cell-culture vessel with thin culture-medium layer of large surface area provides exchange of nutrients and products of metabolism with minimal agitation. Rotation causes averaging of buoyant forces otherwise separating components of different densities. Vessel enables growth of cells in homogeneous distribution with little agitation and little shear stress.

Wolf, David A.↗
NASA NTRS1992

Calculations of separated vortex flows at low speed for low-aspect-ratio wings

An implicit finite-difference scheme has been developed for solving three-dimensional incompressible Navier-Stokes equations. Computations for complicated vortical flows past several sharp- and round-edged delta and double-delta wings at high angles of attack and sideslip are discussed. Computed results demonstrate the effectiveness of the present method and show good agreement with experimental data.

Liu, C. H.↗