2004 年 52 巻 611 号 p. 535-540
A wing rock is known to be a self-excited rolling oscillation of a delta wing that is induced by unsteady aerodynamic forces. In this study, free-to-roll simulations are carried out by incorporating time-accurate computational fluid dynamics with an equation of motion of a wing. A limit cycle oscillation and the histogram of a hysteresis in the rolling moment, which has four peaks within one cycle, are successfully simulated. The strength of the leading-edge vortices at a fixed roll angle is rather different from that during the wing rock especially at large angular velocities and that causes the characteristics behavior of the unsteady moments.