Abstract
Three-dimensional morphologies of Madracis mirabilis were obtained using X-ray computed tomography scanning techniques. The morphologies were used to simulate the flow patterns around the colony. In the simulations, the thin-branching low-flow morph with a relatively larger branch-spacing was compared with the more compact high-flow morph of M. mirabilis. For both morphologies, the inside-colony flow velocities were computed for Reynolds numbers ranging from 154 to 3840. In the high-flow morph, it was found that in the range of investigated Reynolds numbers a stagnant region develops within the colony, whereas in the low-flow morph the stagnant region disappeared. Experiments done under natural conditions suggest that a morph is adapted to a certain external flow velocity and develops a stagnant region below a particular threshold for the external flow velocity. When the external flow velocity exceeds a certain threshold, which is characteristic for the growth form, the core velocity becomes equal to the external velocity. A potential application of a profile of core velocities for a range of Reynolds numbers for a certain morph is the prediction of the optimal external flow velocity for a certain morph, and this can be used to assess the state of the physical (palaeo-) environment.
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Selected References
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- Heijs AW, Lowe CP. Numerical evaluation of the permeability and the Kozeny constant for two types of porous media. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 1995 May;51(5):4346–4352. doi: 10.1103/physreve.51.4346. [DOI] [PubMed] [Google Scholar]
- Kaandorp J. A., Sloot P. M. Morphological models of radiate accretive growth and the influence of hydrodynamics. J Theor Biol. 2001 Apr 7;209(3):257–274. doi: 10.1006/jtbi.2001.2261. [DOI] [PubMed] [Google Scholar]
- Kaandorp JA, Lowe CP, Frenkel D, Sloot PM. Effect of Nutrient Diffusion and Flow on Coral Morphology. Phys Rev Lett. 1996 Sep 9;77(11):2328–2331. doi: 10.1103/PhysRevLett.77.2328. [DOI] [PubMed] [Google Scholar]
- Kandhai D., Hlushkou D., Hoekstra A. G., Sloot P. M. A., Van As H., Tallarek U. Influence of stagnant zones on transient and asymptotic dispersion in macroscopically homogeneous porous media. Phys Rev Lett. 2002 May 24;88(23):234501–234501. doi: 10.1103/PhysRevLett.88.234501. [DOI] [PubMed] [Google Scholar]
- Lowe CP, Frenkel D. Do Hydrodynamic Dispersion Coefficients Exist? Phys Rev Lett. 1996 Nov 25;77(22):4552–4555. doi: 10.1103/PhysRevLett.77.4552. [DOI] [PubMed] [Google Scholar]