模型風車実験用の簡易で安価な小型風洞装置の製作と特性計測

With the aim of doing the performance comparison experiments of small models of Vertical Axis Wind Turbine(VAWT), a simple and low-cost small wind tunnel without a contraction nozzle has been constructed. This wind tunnel is simply composed of an axial blower, a wide-angle diffuser, and a flow conditioner part which includes an aluminum-honeycomb and three stainless steel screens. The total length of the wind tunnel is 2.6m and the outlet is a square of 0.8m х0.8m. The maximum wind speed measured at the center of the outlet is 4.7m/s. The uniformity of wind speed distribution is 4.7%（RMS / mean speed) and the mean turbulence intensity is 4.4%, in the core region (-0.3m ≤ Y or Z ≤ 0.3m) at the outlet (X＝0.01m). The total cost of the wind tunnel was about 630,000 JPY (about 8,000 USD).