PIV and BIV Measurements of Roller in Hydraulic Jumps

Abstract

Park, M.; Kim, H.S.; Choi, S., and Ryu, Y.-U., 2021. PIV and BIV measurements of roller in hydraulic jumps. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 56–60. Coconut Creek (Florida), ISSN 0749-0208. This study performed an experimental investigation on roller in hydraulic jump. Based on the similarity between tidal bore and hydraulic jump, the turbulence flow and free surface fluctuation of the hydraulic jump roller were analyzed with adjustment of downstream water level. To obtain instantaneous flow field including bubbly flow, PIV and BIV technique with shadowgraphy was applied. The result found that the streamwise turbulent flow was dominated at the lower part of roller while the vertical turbulence increased near the water surface of roller in hydraulic jump. The water level showed a large fluctuation as a hydraulic jump occurred. These challenges identified the detailed view of velocity and free surface of roller region can be provided using image analysis.