57 巻 (1991) 533 号 p. 8-13
A forced reattachment of the shear layer separated from cylinder can be realized by setting up a small cylinder in the shear layer near the main cylinder. The properties of the reattachment jet on the rear face of the cylinder have been experimentally investigated. We found that the critical conditions of the forced reattachment coincide with that of a turbulent wall jet along a circular cylinder and a jet on a circular cylinder immersed in uniform flow. The properties of the reattachment jet are similar to those of the turbulent wall jet along the circular cylinder; the velocity distributions of both are nearly equal. The near wake behind the reattachment jet is almost stagnant and the lift acting on the cylinder is proportional to the momentum coefficient of the jet.