The aircraft is immersed in the external flow field, and the fluid flowing across the airfoil surface will generate pressure in the direction perpendicular to the surface and shear force in the direction parallel to the surface. The compressible external flow field during the ascent of the vehicle is discussed in another paper by Lu and Guangming in this paper, we study the incompressible external flow field. The properties of a specific external flow field are different from each other, which means the corresponding parameters that need to be confirmed in the simulation prediction are also different and piecewise analysis is required. According to different flight velocities, the vehicle will suffer different external flow environments, including incompressible external flow fields and compressible external flow fields. The accurate prediction of flight environments plays a vital role in designing and optimizing aircraft. Considering the error ratios comprehensively, the simulation configurations of sharp trailing edge + 20 m far-field distance + SA/SST/SST/SST/SST/SA turbulence model obtains optimal simulation effects. In particular, a greater number of data points adopted into the definition formula is not necessarily better. As to the corresponding modeling methods, the NACA4 and the definition formula are preferred, the choice of which depends on the studied range. Unlike under low Reynolds numbers, the analysis results show that although the accuracy difference between the sharp trailing edge and the blunt trailing edge decreases as the attack angle range increases, the former is preferred in all studied ranges. The same number of structured grids are generated by a unified grid strategy and the SST k-omega and the Spalart–Allmaras models are adopted to solve the NS equations to realize the numerical simulations. In this paper, two trailing edge shapes are designed by three modeling methods and combined with three far-field distances to establish eighteen two-dimensional external flow fields. Currently, influence analysis of simulation parameters, especially the trailing edge shape and the corresponding modeling method on the force coefficients of NACA0012 under a high Reynolds number, is relatively sparse.
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