Abstract
This paper conducts a 2D geometry trade study of flows with high adverse pressure gradients sustained by Co-Flow Jet (CFJ) active flow control (AFC) to achieve the optimal aerodynamic efficiency of a Cylinder. The flow field is solved using the steady Reynolds Averaged Navier-Stokes (RANS) equations with the two-equation κ-ω Shear-Stress Transport turbulence model. At mach 0.02, the conditions for this study simulate the ones present in for a cargo ship traveling at routine speeds. The optimal CFJ cylinder studied showed peak values of lift up to 11.70, drag down to 0.01, power coefficient down to 0.49, and aerodynamic efficiency of 23.38. This optimal location occurs when the suction slot is located at 107.5◦ azimuth and injection slot at -10◦ azimuth. Compared to the baseline CFJ cylinder, it is recommended to move the suction slot upstream 5◦ and injection slot upstream 10◦ to achieve this performance increase. While the values generated are substantial improvements, the optimal case still lies on the edge of the tested data set, so the trend merits further study to investigate if there are even better locations that can be found further upstream, or if the performance drops off. All flows tested reached a stable solution after 500,000 iterations with slightly more than 2 orders of convergence. Due to its ability to maintain attached flow in the presence of an extreme adverse pressure gradient, the CFJ offers an effective method of active flow control with the potential to be far more effective than other active flow control devices.