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In the present paper the experimental investigations of flow across staggered tube bundles in waste heat boiler are conducted by mans of PIV (Particle Image Velocimetry) system. Flow visualization and velocity distribution of the wake between different cylinders are measured in detail. It is concluded that there are still Von Karman vortices in the wake and the phenomena of vortex shedding, pairing, merging are observed in the flow. The Von Karman vortices can’t fully developed because of the existence of the downstream cylinder There is interaction between main streams and vortices, and the development of the vortex is enhanced by this interaction. Meanwhile some statistical results are performed. The distribution of correlated variables of the velocity fluctuations u’ u’, u’ v’, v’ v’ and the space correlation coefficients are obtained.
In the present paper the experimental investigations of flow across staggered tube bundles in waste heat boiler are conducted by mans of PIV (Particle Image Velocimetry) system. Flow visualization and velocity distribution of the wake between different cylinders are measured in detail. It is is that that there are still Von Karman vortices in the wake and the phenomena of vortex shedding, pairing, merging are observed in the flow. The Von Karman vortices can not fully developed because of the existence of the downstream cylinder There is interaction between main streams and vortices , and the development of the vortex is enhanced by this interaction. The distribution of correlated variables of the velocity fluctuations u ’u’, u ’v’, v ’v’ and the space correlation coefficients are .