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Poling, David R.

Publications and source records attributed to Poling, David R..

4 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1990

Blade-vortex interaction experiments - Velocity and vorticity fields

The blade-vortex interaction problem is studied experimentally with laser-Doppler velocimetry. Vortices are generated by pitching a NACA 0012 airfoil about its quarter chord and a target airfoil is mounted two chord lengths downstream of the vortex generator. LDV measurements are obtained in the neighborhood of the target airfoil's leading edge and ensemble-averaged velocity vector fields and vorticity contours are constructed. Vorticity fields are also constructed from velocity time records by assuming that, over short distances, the vorticity propagates with the local velocity. This assumption allows the blade-vortex interaction to be simulated from very few measurements.

Wilder, Michael C.↗
NASA NTRS1988

Two-dimensional interaction of vortices with a blade

The problem of blade-vortex interaction is studied experimentally and numerically. Vortices are generated in the laboratory by pitching an airfoil upstream of the model. LDV measurements are obtained in the neighborhood of the leading edge of the airfoil. Ensemble-averaged velocity vector fields and vorticity contours are thus constructed. A vortex is modeled numerically by a cloud of discrete ideal point vortices. The problem is solved via a Joukowski transformation. The interaction of distributed vorticity with the leading edge of the airfoil is examined.

Poling, David R.↗
NASA NTRS1987

Blade-vortex interaction

A conformal transformation and discrete vortex dynamics are used to calculate the interaction of a blade with vortices drifting with the free stream. An unsteady Kutta condition is employed to dictate the strength of vortices shed at the trailing edge. Instantaneous pressure distributions are calculated and compared with earlier experimental and analytical data.

Poling, David R.↗