Yang, Chun-YaoChun-YaoYangLee, Yaw-HueiYaw-HueiLeeChow, Yi-ChihYi-ChihChow2021-03-082021-03-082019-0911th International Workshop on Ship and Marine Hydrodynamics (IWSH2019), Paper 59http://hdl.handle.net/11420/9027The horseshoe vortex (HSV) usually induces undesirable effects like noise, vibration, and drag. Therefore, the HSV is not only of academic interest but also a critical engineering issue. We used two high-speed cameras with prolonged exposure time to record the pathlines of the seeding particles illuminated by a continuous-wave laser. These particle pathlines constitute a very clear visualization of flow structures, especially vortical structures, i.e. vortices. Next, we used this PIV-based flow visualization technique to study the kinematics of HSV associated with a surface-mounted NACA66 hydrofoil for a Reynolds number of 8,820 (based on the maximum thickness of the hydrofoil and the free-stream velocity). We observed six kinematic patterns of HSV, and measured the occurrence probability for each pattern: (i) steady (17%), (ii) amalgamating (26%), (iii) breakaway (31%), (iv) transition (12%), (v) random (8%), and (vi) roll-up (6%). The naming and definitions of patterns (i) to (v) are adopted from Younis et al [1]. We also found that the HSV adjacent to the hydrofoil surface rises as it extends downstream.enhttp://rightsstatements.org/vocab/InC/1.0/Coherent structureFlow visualizationHorseshoe vortexKinematic patternTechnikConference Paper10.15480/882.335310.15480/882.3353Fluiddynamik und Schiffstheorie M-8Other