ABSTRAKT

Experimental study on the turbulent flow in a circular pipe with a semi-circular orifice has been conducted. The velocity was measured by a stereo PIV system that provided the three components of mean velocity in as well as six components of the Reynolds stress on the cross section of the pipe at different streamwise locations. The oncoming flow was confirmed to be a typical fully developed turbulent flow. The flow behind the semi-circular orifice was found to be strongly turbulent, associated with secondary flow. The ambiguity in the experiments was carefully addressed, and it was found that the measurement conducted either with or without the orifice was found to be equally accurate.