###### Abstract
Furthermore, they emphasized that turbulence intensity has a significant impact on the simulation of the transonic shock buffet. However, the DDES results showed significant deviations in the lift coefficient power spectral density when compared to experimental data. [PERSON] [12] conducted a numerical study on the same shock wave-boundary layer interaction phenomena with IDDES based on the SST model. They proposed a flow control method using vortex generators to suppress the transonic shock buffet. The computational results demonstrated the effectiveness of this control measure. ZDES avoids the issues of Grid-Induced Separation (GIS) [13] and Modeled-Stress Depletion (MSD) by specifying RANS and LES regions in the computational domains. Furthermore, ZDES not only circumvents the problems associated with the Gray-Area [14] but also allows the application of different DES modes to corresponding flow separation types. This flexibility in using different DES modes for various separation regions in the same flow field enhances the analysis of turbulent structures in separation areas. Thus, it is suitable for investigating the complex flow phenomenon of the transonic buffet. [PERSON] [15] conducted a numerical simulation on the OAT15A supercritical airfoil with ZDES based on S-A model. The results demonstrated that the method offered a superior simulation accuracy compared with URANS and DES. ZDES is capable of predicting the transonic shock buffet frequency, whereas the URANS and DES required higher angles of attack to capture this frequency. [PERSON] [16] utilized the AZDES method based on the S-A model to investigate the transonic buffet in the CRM model. A comparison with the DDES revealed that DDES led to lower-frequency motion and failed to capture the streamwise convective features of the buffet. The AZDES proved to be more suitable than DDES for reproducing the observed three-dimensional transonic vibrations on the CRM model within the frequency range of the experiment. [PERSON] [17] simulated the transonic shock buffet using ZDES based on an unstructured mesh. They compared the effects of the turbulence model and mesh resolution on the prediction results. The results indicated that grid density had a minimal impact on the prediction of shock wave position. Furthermore, they found that ZDES with a wall model performed well in predicting the transonic buffet. In summary, the ZDES method is more accurate in predicting transonic shock buffet phenomena. However, existing studies are insufficient in exploring the related physical mechanisms, making it necessary to conduct numerical simulations using the ZDES method to analyze the evolution of flow separation during the shock motion process. The solver used in this study was developed based on NASA's CFL3D open-source program. This study utilized ZDES based on the SST model to numerically simulate the transonic shock buffet for the OAT15A airfoil. The computational results were then compared to those obtained from the DDES, IDDES, and experiments, aiming to evaluate the modeling capabilities of ZDES. This study aims to investigate the unsteady phenomena and the corresponding physical mechanisms present during the shock oscillation process, which provides a reference for using the ZDES method to predict complex flow separation problems in engineering practice.