

Stability might be the other important target besides power efficiency. At this work, we focus on examining air dynamic stability of vertical axis wind turbine (VAWT). While our aim is on stability, we will consider it in instability aspect, specifically by measuring turbulence. The quantities are including turbulence kinetic energy, intensity, dissipation and production. Three representative airfoils have been selected, which are NACA0012, NACA23012 and NACA2412. The turbulence generated around these airfoils would be compared at different stages of running, at TSR of 0, 2, 5 and 7. Every position of the airfoil is taken into account, 360 degrees with interval of 5. Here we will apply static analysis instead of transient one because we attempt to eliminate some other effect of air flow in the meantime acquiring higher computation accuracy. At first, we would scrutinize some fundamental principles of turbulence theory. The theory is based on the structure of statistics. Unfolded, there is the kinetic energy equation that leads to the basic quantities mentioned above. Each quantity has certain meaning and role in turbulence. Then we will resent the computation method and results.