دورية أكاديمية
Measurements of the solid-body rotation of anisotropic particles in 3D turbulence
| العنوان: | Measurements of the solid-body rotation of anisotropic particles in 3D turbulence |
|---|---|
| المؤلفون: | Guy G Marcus, Shima Parsa, Stefan Kramel, Rui Ni, Greg A Voth |
| المصدر: | New Journal of Physics, Vol 16, Iss 10, p 102001 (2014) |
| بيانات النشر: | IOP Publishing, 2014. |
| سنة النشر: | 2014 |
| المجموعة: | LCC:Science LCC:Physics |
| مصطلحات موضوعية: | turbulence, anisotropic particles, fluid dynamics, particle laden flows, 3D printing, particle tracking, Science, Physics, QC1-999 |
| الوصف: | We introduce a new method to measure Lagrangian vorticity and the rotational dynamics of anisotropic particles in a turbulent fluid flow. We use 3D printing technology to fabricate crosses (two perpendicular rods) and jacks (three mutually perpendicular rods). Time-resolved measurements of their orientation and solid-body rotation rate are obtained from four video images of their motion in a turbulent flow between oscillating grids with ${{R}_{\lambda }}$ = 91. The advected particles have a largest dimension of 6 times the Kolmogorov length, making them a good approximation to anisotropic tracer particles. Crosses rotate like disks and jacks rotate like spheres, so these measurements, combined with previous measurements of tracer rods, allow experimental study of axisymmetric ellipsoids across the full range of aspect ratios. The measured mean square tumbling rate, $\langle {{\dot{p}}_{i}}{{\dot{p}}_{i}}\rangle $ , confirms previous direct numerical simulations that indicate that disks tumble much more rapidly than rods. Measurements of the alignment of a unit vector defining the orientation of crosses with the direction of their solid-body rotation rate vector provide the first direct observation of the alignment of anisotropic particles by the velocity gradients in a turbulent flow. |
| نوع الوثيقة: | article |
| وصف الملف: | electronic resource |
| اللغة: | English |
| تدمد: | 1367-2630 |
| Relation: | https://doaj.org/toc/1367-2630 |
| DOI: | 10.1088/1367-2630/16/10/102001 |
| URL الوصول: | https://doaj.org/article/46c34ea0145d4608a99681d0de68b374 |
| رقم الأكسشن: | edsdoj.46c34ea0145d4608a99681d0de68b374 |
| قاعدة البيانات: | Directory of Open Access Journals |
Full Text Finder | تدمد: | 13672630 |
|---|---|
| DOI: | 10.1088/1367-2630/16/10/102001 |