Abstract: Scale-adaptive simulation of the transonic flow past supercritical wing is carried out for freestream Mach number 0.80, angle of attack 3° and Reynolds number 1×10⁷. By analyzing vortex structure and the distribution of pressure fluctuation on the wing surface, there are three flow states in the wing flow field, namely shock buffet motion, small-amplitude shock motion, and large separation flow under stall conditions. Analysis of pressure power spectral density at probes indicates that all three flow states exhibit low-frequency motion characteristics. Analyzing the distributions of mean pressure coefficient and root-mean-square values of pressure fluctuation on the wing surface of sections under three flow conditions, large separation flow is the main factor causing fluctuations in the lift and drag coefficients of the wing. Through the analysis of proper orthogonal decomposition of the pressure field, for shock wave buffet motion and small amplitude shock wave motion, the dominant mode is related to the shock wave motion and trailing edge disturbance, and the flow is more stable under shock wave buffet condition; For large separated flow, the dominant mode is related to the motion of unstable shock waves and the shedding of vortex structures of different scales. Compared to shock buffet and small-amplitude shock motion, the velocity fluctuation and turbulent kinetic energy in the near-wall region under large separation flow conditions are at higher level, and the turbulent kinetic energy and turbulent kinetic energy production term near the separation region are significantly enhanced. The pressure-dilatation correlation term related to compressibility effects result in more significant turbulence decay in the shear layer instability region. By analyzing the Lamb vector divergence, for small-amplitude shock motion, there are different momentum transport mechanisms on both sides of the shear layer. For shock buffeting motion and large separation flows, due to the instability of the shear layer, a more chaotic momentum transport pattern is present.