Tip vortex core measurements on a hovering model rotor

Thompson, T.L.; Kwon, Oh Joon; Kemnitz, J. L.; Komerath, Narayanan; Gray, Robin B.

doi:10.2514/6.1987-209

Search citation statements

Order By: Relevance

Paper Sections

Select...

Introduction1

Citation Types

Supporting

Mentioning

Contrasting

Year Published

1988

1998

Publication Types

Select...

Article4

Other1

Relationship

Self Cite0

Independent5

Authors

Journals

Cited by 7 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A leading-edge pressure pulse was the dominant feature of the BVI. Detailed velocity measurements in the tip vortex core of a singlebladed model rotor in hover were made by Thompson et al (1987); however, due to the downwash of the rotor, no blade-vortex interaction occurred in this study. The geometry of the problem is so complex that it is impossible to obtain careful velocity measurements around a rotating blade.…”

Section: Introductionmentioning

confidence: 99%

Parallel Blade–vortex Interaction

Wilder

Telionis

1998

Journal of Fluids and Structures

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Parallel Blade–vortex Interaction

Wilder

Telionis

1998

Journal of Fluids and Structures

View full text Add to dashboard Cite

Visualization and measurement of helicopter rotor flow with swept back tip shapes at hover flight using the “flow visualization gun” time line technique

Müller¹,

Nsi²,

Aymard³

et al. 1996

Experiments in Fluids

View full text Add to dashboard Cite

The Flow Visualization Gun (FVG), a novel time line visualization technique, has been used to investigate the flow field of a helicopter rotor with swept back tip shape in hover flight condition. After introducing the FVG-technique, the paper presents some visualization photographs of the rotor blade tip vortices and the rotor downwash. Using orthogonal sets of flow photographs and digital image analysis, the 3-dimensional time line displacement within the flow and the tip vortex structure are determined. The data of 16 time line experiments are interpolated in space and time to obtain velocity data on an evenly spaced 3-dimensional grid. Vorticity contour plots of the flow field show the complex arrangement of the tip vortices of the blade itself and of the preceding blade and some additional vorticity in the direct wake which may form a secondary vortex. Understanding and control of this vorticity distribution is important for the design of new efficient tip shapes. While the FVG technique has been used so far for qualitative investigation of complex flow patterns at local velocities of up to 20 m/s, a good comparison to laser velocimetry data validates the technique as an interesting tool for both qualitative and quantitative investigation.

show abstract