On the Lamb Vector and the Hydrodynamic Charge

Germain Rousseaux; Shahar Seifer; Victor Steinberg; Alexander Wiebel

doi:10.1007/s00348-006-0238-2

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On the Lamb Vector and the Hydrodynamic Charge

Germain Rousseaux·Shahar Seifer·Victor Steinberg·Alexander Wiebel

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Abstract

This work is an attempt to test the concept of hydrodynamic charge (analogous to the electric charge in Electromagnetism) in the simple case of a coherent structure such as the Burgers vortex. We provide experimental measurements of both the so-called Lamb vector and its divergence (the charge) by two-dimensional Particle Image Velocimetry. In addition, we perform a Helmholtz-Hodge decomposition of the Lamb vector in order to explore its topological features. We compare the charge with the well-known Q criterion in order to assess its interest in detecting and characterizing coherent structure. Usefulness of this concept in studies of vortex dynamics is demonstrated.

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Germain Rousseaux, Shahar Seifer, Victor Steinberg, Alexander Wiebel. 2006-06-26. On the Lamb Vector and the Hydrodynamic Charge. https://doi.org/10.1007/s00348-006-0238-2

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