The Effect of the Inclination Angle of a Vortex Generator on Vortex Generation and Heat Transfer Enhancement in a Laminar Boundary Layer

A triangular vortex generator with varying inclination angles(45° − 135°) was installed in front of the heating measurement section in laminar flow. Heat transfer enhancement was evaluated using an IR camera, and flow structures were visualized with the smoke wire method. Results showed that local heat transfer rate increased up to about 60° , after which it decreased with further angle increase. Spanwise comparisons indicated a shift in vortex formation depending on the direction of angle change. Flow visualization confirmed the persistence of longitudinal vortices and their rotation direction. These findings clarify the relationship between vortex generator inclination and heat transfer enhancement.