• International Journal of Fluid Machinery and Systems
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• v.4 no.3
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• pp.341-348
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• 2011

The study of bacterial flagellar swimming motion remains an interesting and challenging research subject in the fields of hydrodynamics and bio-locomotion. This swimming motion is characterized by very low Reynolds numbers, which is unique and time reversible. In particular, the effect of rotation of helical flagella of bacterium on swimming motion requires detailed multi-disciplinary analysis. Clear understanding of such swimming motion will not only be beneficial for biologists but also to engineers interested in developing nanorobots mimicking bacterial swimming. In this paper, computational fluid dynamics (CFD) simulation of a three dimensional single flagellated bacteria has been developed and the fluid flow around the flagellum is investigated. CFD-based modeling studies were conducted to find the variables that affect the forward thrust experienced by the swimming bacterium. It is found that the propulsive force increases with increase in rotational velocity of flagellum and viscosity of surrounding fluid. It is also deduced from the study that the forward force depends on the geometry of helical flagella (directly proportional to square of the helical radius and inversely proportional to pitch).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.6
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• pp.497-504
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• 2015

In this paper, we study the propulsive behavior related to the flagellar motion of bacteria using a spring model. A commercial program was used to conduct simulations, and we verified the numerical technique by setting an additional rotating domain and conducting a parametric study. The numerical results are in good agreement with slender-body theory, although overall, they are not in agreement with resistive-force theory. We confirm the effect of the rotational velocity, pitch, helical radius, fluid viscosity, and, in particular, the distance from the wall on the propulsion of the spring.