PIV measurement of turbulent bubbly mixing layer flow with polymer additives

Bubbly mixing layer with polymer additives is investigated by PIV. The void fraction is 0.5%. The comparison between single-phase and bubbly mixing layer shows that the dynamic development of mixing layer is greatly influenced by the bubble injection. Similar with single phase, the Reynolds stress and vorticity still concentrate in a coniform area of central mixing flow field and the width increases with increasing the Reynolds number. Mean Reynolds stress decreases with bubble injection at high Reynolds numbers and the decreasing of Reynolds stress with polymer additives is much more than that in a pure water case. There is an obvious decreasing to the peak value of vorticity when bubbles are injected into the fluid, and the influence on the viscoelastic fluid is smaller than that on the pure water.