This paper presents the dynamic behavior of a fluidic diode (FD) subjected to periodic flow (oscillatory flow). This study captures the transient performance of the FD, which a steady-state flow analysis cannot predict, helping in better prediction of the performance and in designing an efficient model for the real sea flow profile. The FD offers variable resistance to the flow depending on its geometrical shape. Its performance is given by diodicity, which is a ratio of pressure drop in reverse to forward flow. It is used with the turbine to improve flow rectification. The numerical model is solved for three-dimensional unsteady Reynolds-Averaged Navier Stokes equations using ANSYS Fluent 16.1. The article presents the FD's detailed transient flow behavior and performance with the turbine. The FD operating in oscillatory flow performed better than in a steady flow because of the dynamic nature of the fluid. The analytical study shows that the performance of FD with turbine performed better at lower flow-coefficient.