Organisers

• Vladimir Lobaskin (University College Dublin)
• Roland Netz (TUM Munich)
• Lydéric Bocquet (Université Claude Bernard-Lyon 1)

Supports

 SimBioMa

Description

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Computer simulations can provide valuable insight into complex biological systems that involve the interaction of elastic structures with a viscous, incompressible fluid. The field of biological fluid dynamics presents a number of challenges in addition to those traditionally faced in computational fluid dynamics. In order to model the motion of living organisms it is necessary to capture time-dependent geometries with large structural deformations. Usually, the shape of the elastic structures are not preset, but determined by the fluid dynamics, which requires a modification of standard continuum mechanics schemes. On a larger lengthscale, the major challenges in biological fluid dynamics include modeling self-organization in active, hydrodynamically coupled systems such as beating cilia or bacterial swarms. It is obvious, that neither continuum mechanics methods nor molecular simulations are well suited for solving these problems and, therefore, a development of efficient hybrid or mesoscale methods is necessary.

The field of biological fluid dynamics is now rapidly expanding towards microscopic biomimetic systems. Recent advances in micromanipulation techniques made it possible to construct artificial swimmers mimicking the microbial self-propulsion mechanisms. The first working microswimmer imitating the flagellum beating was reported recently by a French group. Moreover, a number of realistic implementations of DNA-based, and colloidal micro- and nanomachines were suggested. The modern technology thus opens a broad avenue for development of microscopic self-propelling machines, the use of which is already planned for a variety of bio-medical, chemical and microfluidic applications. The field of biomimetic micromachines also poses new challenges, such as design and optimization of reliable self-propulsion mechanisms or modeling time-dependent boundary conditions in the microfluidic simulations.

Scientific Objectives

We would like to bring together the community working actively in the field of biological fluid dynamics, facilitate the ideas exchange between the groups working in theory, experiment and simulation, and concentrate an effort on developing simulation methods along the following main directions:
· Coupling fluid flows to motion of elastic bodies
· Fluid dynamics at active interfaces and time-dependent boundary conditions
· Hydrodynamic coupling and self-organization of active filaments and microswimmers
· Mechanics and novel mechanisms of self-propulsion at low Reynolds numbers

References

1. E. Purcell, The efficiency of propulsion by a rotating flagellum Proc. Natl. Acad. Sci. 94: 11307-11311 (1997)
2. L. E. Becker, S. A. Koehler, H. A. Stone, On self-propulsion of micro-machines at low Reynolds number: Purcell's three-link swimmer, J. Fluid Mech. 490, 15 (2003).
3. A. Shapere and F. Wilczek, Self-propulsion at low Reynolds-number, Phys. Rev. Lett. 58, 2051 (1987)
4. A. Shapere and F. Wilczek, Geometry of self-propulsion at low Reynolds-number, J. Fluid Mech. 198, 557,585 (1989).
5. H. A. Stone, A. D. T. Samuel, Propulsion of microorganisms by surface distortions, Phys. Rev. Lett. 77, 4102 (1996).
6. B. U. Felderhof and R. B. Jones, Small-amplitude swimming of a sphere, Physica A 202, 119 (1994).
7. R. Dreyfus, J. Baudry, M. L. Roper, M. Fermigier, H. A. Stone, J. Bibette, Microscopic artificial swimmers, Nature 437, 862 (2005)
8. M. Manghi, X. Schlagberger and R.R. Netz, Propulsion with a Rotating Elastic Nano-Rod, Phys. Rev. Lett. 96, 068101 (2006)
9. A. Najafi, R. Golestanian, Simple swimmer at low Reynolds number: Three linked spheres, Phys. Rev. E 69, 062901 (2004).
10. S. Camalet, F. Julicher, J. Prost, Self-organized beating and swimming of internally driven filaments, Phys. Rev. Lett. 82, 1590-1593 (1999)
11. P. E. Lammert, J. Prost, R. Bruinsma, Ion drive for vesicles and cells, J. Theor. Biology 178, 387-391 (1996)
12. J. E. Avron, O. Gat, O. Kenneth, Optimal swimming at low Reynolds numbers, Phys. Rev. Lett. 93, 186001 (2004)
13. W. Ebeling, Nonequilibrium statistical mechanics of swarms of driven particles,
Physica A 314, 92-96 (2002)
14. U. B. Felderhof, The swimming of animalcules, Phys. Fluids 18, 063101 (2006)
15. I. M. Kulic, R. Thaokar, H. Schiessel, Twirling DNA rings - swimming nanomotors ready for the kickstart, Europhys. Lett. 72, 527 (2005).
16. R. Cortez, N. Cowen, R. Dillon, L. Fauci, Simulation of swimming organisms: Coupling internal mechanics with external fluid dynamics, Computing in Science and Engineering 6, 38-45 (2004)
17. I. Llopis, I. Pagonabarraga, Dynamic regimes of hydrodynamically coupled self-propelling particles, Europhys. Lett. 75, 999 (2006)
18. W. F. Paxton, A. Sen, and T. E. Mallouk, Motility of Catalytic Nanoparticles through Self-Generated Forces, Chemistry - A European Journal 11, 6462 (2005)
19. N. Mano and A. Heller, Bioelectrochemical Propulsion, J. Am. Chem. Soc. 127, 11574 (2005)
20. R. Golestanian, T.B. Liverpool and A. Ajdari, Propulsion of a molecular machine by asymmetric distribution of reaction-products, Phys. Rev. Lett. 94, 220801 (2005)