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Updated: Jul 2, 2026
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Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence
Published on: June 24, 2016
Technique for the measurement of spatial vorticity distributions
M S Francis1, D A Kennedy, G A Butler
1Mechanics Division, Frank J. Seiler Research Laboratory, U. S. Air Force Academy, CO 80840, USA.
The Review of Scientific Instruments
|May 1, 1978
Summary
This study introduces a simple hot-wire anemometry method to measure spatial vorticity in fluid flows. The technique accurately quantizes circulation, validated by trailing vortex experiments and applicable to unsteady flows.
Area of Science:
- Fluid dynamics
- Aerodynamics
- Experimental methods
Background:
- Accurate measurement of spatial vorticity is crucial for understanding complex fluid flow phenomena.
- Existing methods may have limitations in certain flow regimes or complexity.
Purpose of the Study:
- To present a straightforward and accurate method for measuring mean spatial vorticity content.
- To evaluate the circulation associated with spatial contours in fluid flows.
- To demonstrate the method's applicability and accuracy through experimental validation.
Main Methods:
- Utilized an "X"-geometry hot-wire probe and a linearized anemometer system.
- Employed a precision probe traversing mechanism for spatial contour evaluation.
- Computed measurement errors in exact and linearized forms.
Main Results:
- The described technique effectively measures mean spatial vorticity and circulation.
- Minimal measurement errors were achieved with careful selection of integration paths.
- Experimental validation using an isolated trailing vortex and wing trailing edge flows confirmed accuracy.
Conclusions:
- The presented method offers a reliable approach for spatial vorticity measurement in various flow conditions.
- The technique is validated against existing theories and experimental data.
- The method shows potential for extension to periodically driven unsteady flows.
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