This thesis presents the development of a device for generating electrical energy from vortices formed in water flow behind a bluff body. Development was carried out in two stages. A laboratory system was used to examine the influence of body geometry and construction settings, and the findings were applied to a larger prototype. A cylinder and a profiled hydrofoil were used as bodies in the flow. The device consists of the flow-exposed body, an elastic suspension and a mechanical transmission that converts oscillatory motion into shaft rotation.
Experimental evaluation focused on the mechanical stage of energy conversion. Mechanical power at the shaft was determined from measured torque and rotational frequency. Measurements were performed at a water-flow velocity of 0.9 m/s. With the hydrofoil, the highest average mechanical power was 5.48 W and the highest measured value was 10.14 W. With the cylinder, the corresponding values were 1.09 W and 2.09 W.
Compared with the laboratory system, the prototype achieved approximately 2.94 times higher average mechanical power and about four times higher average torque, while its rotational frequency was 27 % lower. The results show that performance is strongly influenced by body geometry, elastic suspension and mechanical-transmission settings.
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