Abstract: One of many interesting research activities in biofluidmechanics is dedicated to investigations of locomotion in water. Some of propulsion mechanisms observed in the underwater world are used in the development process of underwater auto-nomic vehicles (AUV). In order to characterise several solutions according to their manoeuvrability, influence on the sur-rounding fluid and energetic efficiency, a detailed analysis of fin-like movement is indispensable.
In the current paper an analysis of undulatory, oscillatory and combined fin-like movements by means of numerical simulation is carried out. The conservation equation of mass and the conservation equation of momentum are solved with the Finite Volume Method (FVM) by use of the software CFX−10.0. The undulatory and oscillatory fin movements are modelled with an equation that is implemented within an additional subroutine and joined with the main solver. Numericalsimulations are carried out in the computational domain, in which one fin is fixed in a flow-through water duct. Simulations are carried out in the range of the Re number up to 105. The results show significant influence of applied fin motion on the velocity distribution in the surrounding fluid.

Key words: fin-like movement, biofluid dynamics, fish propulsion, computational fluid dynamics