Investigation on flow field behind an orifice under combined effect of swirling flow and orifice bias

Flow accelerated corrosion in a pipe is an important topic of interest associated with pipe wall thinning phenomenon in highly aged nuclear power stations. In the present study, the velocity field behind an orifice in a pipe is studied by PIV measurement at various combinations of swirling-flow intensity and orifice bias. The flow observations along the flow axis and those across the pipe indicate that the orifice bias is so influential on the flow behind the orifice at strong swirling-flow. (author)