The Takahashi laboratory is divided into two groups of wind group and Leo group according to the nature of the fluid. Each group is divided according to the research subject.
  • Wind Team ： Research on fluid related vibration for Newtonian fluid such as water and air.
  • Rheology Team ： Research on rheology (complex fluid) for non-Newtonian fluid such as surfactant, liquid crystal, polymer solution.

Wind Team Longitudinal Windmill Watermill Group

Research background

As shown in Fig.1, "longitudinal vortex" having a rotation axis parallel to the main flow direction occurs periodically from the top and bottom of the cylinder by providing a certain clearance in the downstream of the column elastically supported in the fluid and arranging the cross plates crosswise.
In previous studies, we have been conducting research to utilize "longitudinal vortex excitation" which is a resonance phenomenon due to a longitudinal vortex as a power source for power generation.

karman Vortex
karman Vortex
Fig. 1 The system of cylinder/flat-plate and longitudinal vortices
We got inspiration from the mechanism by which this longitudinal vortex occurs. As shown in Fig.2, we developed a cylindrical wing-type wind turbine with a flat plate in a ring shape by attaching a drive shaft for rotation to the cylinder of the front flow. This wind turbine generates a lift by generating a longitudinal vortex steadily from one side of a cylinder, and obtains rotational force. This wind turbine using a cylinder is completely different from a wind turbine using a conventional airfoil. Therefore, it is thought that advancing R & D will cause major change and profit in the study of windmills and fluid dynamics.

karman Vortex
karman Vortex
Fig.2 Wind turbine with circular cylinder blades
It is known that this cylindrical wing turbine is driven by the steady generation of lift by longitudinal vortex. However, it is a new research, there is no prior research, and there are few references. Therefore, it is required to elucidate the power characteristics of rotation under various conditions.
In this research, we aim to elucidate the basic power characteristics of the research on cylindrical wing turbines.

Simulation of longitudinal wind/water turbine driven by vertical vortex
（D3 NAKATA Hideki）

Effect of geometric factors on the power characteristics of longitudinal wind/water turbine driven by vertical vortex
（M2 NISHIMURA Mamoru）

Development of longitudinal wind/water turbine driven by vertical vortex
（M2 SUGATA Kohei）

Elucidation of the influence of shape factors on the size effects of longitudinal wind/water turbine driven by vertical vortex
（M1 KURODA Ryutaro）

Improvement of power characteristics of longitudinal wind/water turbine driven by vertical vortex using wind lens
（M1 SHIMOHIGASHI Humiya）

Development of lift devices powered by vortex
（B4 SADAOKA Ryuga）

Development of lift devices powered by vortex
（B4 ENKHLUUN BOLDBAATAR）