Abstract
This paper reports the experimental study for the passive yaw behavior of horizontal axis small wind turbines.
A velocity of yaw angle in small wind turbine is given as a design value in HS C 1400-2, in which themaximum velocity of yaw angle is prescribed as lrad/s.However, in case of small wind turbines of less than adiameter of 2m, the yaw angular velocity has possibilities larger than l rad/s. Until now, on this connection, therehad been no report on systematic experiments concerning about these design values.
Therefore to clarify a design value of passive yaw for small wind turbines, the authors conducted a theoreticalestimation as well as a wind tunnel test.The model of wind turbine tested is a diameter of im, blade number of 5, solidity of 0.26 and 2 type tail fins (large and small).We evaluate the yaw behavior for changing number of rotorrevolution, area of tail fin and wind speeds.
The yaw angular velocity becomes larger with increase of wind velocity and area of tail fin.The larger therotor revolution, the smaller becomes the tendency.Furthermore, the maximum yaw angular velocity became3.84rad/s which exceeds the conventional design value of 1 rad/s at the wind speed 10m/s.
