抄録
This paper is described an experimental study on circular duct flow with wirling flow. The swirling flow is very important for gas turbine combustor, fornaces, etc.
In this study, the velocity and flow pattern of the swirl flow in a circular duct is measured using a laser Doppler Velocimeter (LDV) when the expansion ratio(D/d) in circula duct is varied from 1.5 to 3.0.Further, the flow visualization is carried out using a streamer, sparktracting method and alminium powder method.
From these results, the present study clarifies the flow patterns and the size and shape of recirulation, eye of vortex and sub-recirculation zones for the expansion ratio.