An experimental method, the so-called color-coded Digital Particle Tracking Velocimetry system was set up in this study to investigate viscous flow through an artificial bileaflet valve with three different opening angles, 5°, 30°, and 45°, respectively. An oscilloscope that generated stable wave speed was taken to calibrate measuring result of the equipment. Besides, a fully developed pipe flow case was used to check the reliability of experimental system, and a statistical t-test was performed to further enhance the comparison of analytical solution and measurement. From the details of randomly distributed velocities, interpolated velocity components, and velocity profiles for the studied flow case, it could be observed that three jetlike flows through upper, central and lower parts of the two leaflets occurred in this flow configuration. Due to the effect of shear layer at wall boundary and at valve wake, the jet-like flows interfered with each other, and caused that the larger the opening angle, the stronger the recirculation region at downstream of valve structure. As a result, the velocity distributions exhibited more oscillating phenomenon in both axial and radius directions for larger opening angle case. From error analysis, although these measured results might involve some uncertainties and incompleteness, they might provide basic flow characteristics in this type of flow case and relative applications
Kerh, Tienfuan; Chen, Yen-Ming; and Tsou, I
"MEASUREMENT OF VELOCITY DISTRIBUTION FOR FLOW THROUGH A BILEAFLET VALVE USING COLOR-CODED DIGITAL PARTICLE TRACKING VELOCIMETRY,"
Journal of Marine Science and Technology: Vol. 13
, Article 1.
Available at: https://jmstt.ntou.edu.tw/journal/vol13/iss1/1