## 1 Introduction
The study shows that the NACA0012 generates a higher \(C_{l}\) at \(R_{e}\) of 0.283 million and 0.378 million, while this occurs at \(R_{e}\) of 0.189 million for the flat plate. In terms of the blunt trailing edge, Ref. [16] adopts RANS methods and the \(R_{e}\) is 1 million. The results illustrate that the blunt trailing edge blade profile is viable for connecting structural requirements with aerodynamic performance in designing future wind turbine rotors. Ref. [17] extracts crucial quantities of the aerodynamic characteristics of a NACA0012 airfoil with the blunt trailing edge by a data-processing method, which uses the large-eddy model and an \(R_{e}\) of 0.4 million. Through blunt trailing edge modification, the change of aerodynamic characteristics of NACA0012 is studied in Ref. [18] and the spectral analysis indicates a decrease of shedding intensity with a shorter trailing edge, with a reduction of up to 57%. In Ref. [19], the authors study the aerodynamic performance of the inflatable wing at an \(R_{e}\) of 3 million, and the turbulence model is SST k-omega. The results show a loss of performance to a certain degree compared with the blunt trailing edge; the closer the shape, the smaller the loss of aerodynamic performance. In summary, the researches mainly focus on the influence of geometrical changes on the force coefficients based on one trailing edge shape, and the geometrical changes include making wavy, cavity, gurney flap, cut-in sinusoidal, step, shorten, and inflatable shapes. However, the focus on the influence of the two trailing edge shapes on the simulation accuracy of force coefficients has been rarely explored, only a few papers underline the shape comparative analysis. Ref. [20] conducts a comparative study on the force coefficients under the conditions of \(R_{e}\) of 0.189 million, 0.283 million, and 0.378 million. However, the compared objects are NACA0012 with a sharp trailing edge and a flat plate. Ref. [21] adopts the two shapes to study the influence on turbine performance under the conditions of \(R_{e}\) of 3 million and the SST k-omega turbulence model, but the influence on the simulation accuracy of NACA0012 force coefficients is not analyzed. Ref. [22] investigates the influence of the trailing edge shape on the force coefficients applying \(R_{e}\) from 0.05 million to 0.1 million with the SST k-omega turbulence model. The result illustrates that the chosen shape of the trailing edge depends on the values of \(R_{e}\) and the AOA. Ref. [23] applies DNSto investigate the effect of the trailing edge shape on the characteristics of the shear layer at an \(R_{e}\) of 0.05 million, but not on the force coefficients. The force coefficients are affected between 3 million and 6 million [4], but the maximum \(R_{e}\) of the above simulations is 3 million, which means that under a high \(R_{e}\) of 6 million, the choice criteria of the trailing edge shape may be different. Unfortunately, appropriate airfoil modeling is the basis for simulation, and the above literature describes few details of the modeling methods and little attention is paid to the influence analysis of modeling methods on the simulation accuracy. Specifically, we can use Airfoil Tools, the NACA4 airfoil generator, and the definition formula to establish the NACA0012 model. For the number of the data points adopted in the definition formula, we have so far not found reliable research literature. In addition, the simulations mentioned above often adopt only one turbulence model with a fixed far-field distance, and the descriptions of the corresponding selection criteria are insufficient. In this paper, six two-dimensional NACA0012 models, including the blunt trailing edge and the sharp trailing edge, are established based on three NACA0012 airfoil modeling methods. Then, combined with three far-field distances, eighteen external flow fields are set. The same number of structured grids are generated by a unified grid strategy and the appropriate values of mesh quality parameters are confirmed.