Abstract
In this paper, the characteristics of different flow structures and their relationship with heat transfer performance are analyzed in two-dimensional rectangular channel with different slot lengths under pulsating flow field. Aiming at the fully developed region of the groove flow path, the aluminum dust method was used to realize the flow visualization. A fixed time photography system built by photoelectric sensors was used to obtain the image of fluid flow structure at eight moments in a cycle, and the numerical simulation results are used to verify the fluid flow structure. It is found that different slot lengths of grooves, different oscillatory fractions and different Strouhal numbers will affect the flow structure of the fluid in the grooves. The occurrence time of strong unstable flow in the groove moves forward with the increase of St number, and the duration of unstable flow also extends with the increase of St number, which also indicates the improvement of heat transfer performance.