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The purpose of this study is to the modeling of the dielectric barrier discharge (DBD) actuator on the Eppler 387 (E387) airfoil in low Reynolds number conditions.

A validated direct-forcing immersed boundary method is used to solve the governing equations. A linear electric field model is used to simulate the DBD actuator. A ray-casting technique is used to define the geometry.

The purposed model is validated against the former studies. Next, the drag and lift coefficients in the static stall of the E387 airfoil are investigated. Results show that when the DBD actuator is on, both of the coefficients are increased. The effects of the location, applied voltage and applied frequency are also studied and find that the leading-edge actuator with higher voltage and frequency has better improvement in the forces. Finally, the dynamic stall of the E387 with the DBD actuator is considered. The simulation shows that generally when the DBD is on, the lift coefficient in the pitch-up section has lower values and in the pitch-down has higher values than the DBD off mode.

It is demonstrated that using the DBD actuator on E387 in the low Reynolds number condition can increase the lift and drag forces. Therefore, the application of the airfoil must be considered.

The results show that sometimes the DBD actuator has different effects on E387 airfoil in low Reynolds number mode than the general understanding of this tool.

The purpose of this study is simulation of dynamic stall behavior around the Eppler 387 airfoil in the low Reynolds number flow with a direct-forcing immersed boundary (DFIB) numerical model.

A ray-casting method is used to define the airfoil geometry. The governing continuity and Navier–Stokes momentum equations and boundary conditions are solved using the DFIB method.

The purposed method is validated against numerical results from alternative schemes and experimental data on static and oscillating airfoil. A base flow regime and different vortices patterns are observed, in accordance with other previously published investigations. Also, the effects of the reduced frequency, the pitch oscillation amplitude and the Reynolds number are studied. The results show that the reduced frequency has a major effect on the flow field and the force coefficients of the airfoil. On the other hand, the Reynolds number of the flow has a little effect on the dynamic stall characteristics of the airfoil at least in the laminar range.

It is demonstrated that the DFIB model provides an accurate representation of dynamic stall phenomenon.

The results show that the dynamic stall behavior around the Eppler 387 is different than the general dynamic stall behavior understanding in the shedding phase.