Comparison of normal and parallel secondary injection on the cross flow induced vibration of a rough and smooth single cylinder

Abstract EN

This paper reports an experimental investigation on the effect of a downstream secondary injection in the vicinity of an elastically mounted cylinder on the flow induced vibration.

The possibilities of using normal and parallel injection to the cylinder for controlling the flow induced vibration were investigated.

Both smooth and rough cylinders were used.

It was found that at reduced velocities less than 8 the effect of both normal and parallel injections on the flow induced vibrations of the cylinder are negligible for all locations of injection and all surface roughnesses used.

However at reduced velocities greater than 8 the effect of injection is very much dependent on the blowing rates , the location of the injection and the surface roughness of the cylinder.

In general, the normal injection resulted in an increase in the dimensionless vibration amplitude.