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Wilson, L. N.

Publications and source records attributed to Wilson, L. N..

4 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Application of a panel code to unsteady wing-propeller interference

Attention is given to the predictions of unsteady, incompressible, potential flow, on the basis of an extension of Maskew's (1982) low-order paneling method. This approach, which is a nonlinear one in that the small-perturbation approximation is not made, is able to arrive at solutions for such general problems as that of the interference between a two-bladed propeller and a wing. Due to the geometry and flow field in question, a wake-snipping procedure is introduced.

Rangwalla, A. A.↗
NASA NTRS1970

Scattering from condensates in turbulent jets

An analysis is made of the scattering signal levels to be expected from condensed water vapor droplets for crossed-beam instruments operating in the wavelength region. 18 to 4.3 microns. The results show that scattering should not present a problem for the infrared system operating under conditions typical of the IITRI jet facility. Actual measurements made for comparison indicate that scattering levels are appreciable, and presumably result from oil mist added by the facility air compressors.

Wilson, L. N.↗
NASA NTRS1970

Application of crossed beam technology to direct measurements of sound sources in turbulent jets, part 1

The mathematical bases for the direct measurement of sound source intensities in turbulent jets using the crossed-beam technique are discussed in detail. It is found that the problems associated with such measurements lie in three main areas: (1) measurement of the correct flow covariance, (2) accounting for retarded time effects in the measurements, and (3) transformation of measurements to a moving frame of reference. The determination of the particular conditions under which these problems can be circumvented is the main goal of the study.

Wilson, L. N.↗