電動式可変ピッチ機構を有する小型垂直軸風車の二次元非定常流れ解析

A CFD model has been constructed to numerically validate the wind tunnel model of a small vertical-axis wind turbine with a motor-driven variable-pitch mechanism for which we previously reported the result of wind tunnel tests. The test turbine has a radius of 0.18 m, a diameter of the rotating shaft of 0.02 m and three blades with the airfoil section of NACA0015 and chord length of 0.08 m. 2-D Unsteady Reynolds Averaged Navier-Stokes equations with k-k_L-ω turbulence model are solved to simulate a flow around the test turbine rotating at a constant tip speed ratio (TSR) using OpenFOAM. From the simulation results of sixteen cases consisting of two blade conditions of fixed-pitch (FP) and variable-pitch (VP), and eight TSRs of 0.3 to 1.7 with 0.2 increments in one uniform flow of 4 m/s, it has been confirmed that the power coefficients for VP cases become larger than those for FP cases.