High synergy method for near space propeller using co-flow jet control

Based on the Reynolds-averaged Navier-Stokes equations and multi-block grid technology, a numerical simulation is implemented of a high performance airfoil and near space propeller using the co-flow jet (CFJ) flow control method, based on which the mechanism and performance of CFJ technology are studied. In order to quantify the energy efficiency of the CFJ technology, analysis methods of power demand and energy efficiency are proposed. Based on the influence of different jet slot sizes, jet momentum coefficient and other parameters on the CFJ technology performance are investigated, the research of high synergy method for near space propeller by co-flow jet flow control are carried out. It is shown that the numerical simulation results agree well with the experimental data. In different states, CFJ technology can significantly improve the aerodynamic performance of the airfoil: the maximum lift coefficient may increase by 60%-130%, the drag coefficient may be reduced by 100%-440%, and even negative drag coefficient may appear at low angles of attack, so much so that the lift-drag ratio is significantly improved. Also, the airfoil stall characteristics are significantly improved with the stall angle of attack increasing by nearly 10°. Furthermore, the power demand is very low and the energy efficiency is enhanced up to 440%. Finally, due to these improvements, the efficiency of the near space propeller using CFJ technology is increased by more than 5% for the proposed optimal jet slot size and jet momentum coefficient.