Flow System to Detect Transitional Flow Based on Pulsed Doppler Ultrasound Velocity Profiles

A flow circuit test rig has been constructed to determine the critical Reynolds number at which blood flow become turbulent. A Doppler ultrasound velocimeter was used in an in vitro flow system to measure the velocity of water inside a straight pipe in order to determine the critical Reynolds number (Re) at which the flow becomes transitional. Results using water as the working fluid demonstrated flow-transition to turbulence near Re = 2000 which is close to the expected value from literature. Future studies will utilize blood as the working fluid.