Abstract: During hypersonic flight and Earth re-entry, vibrational dynamics of gas molecules, electronic state excitation, and dissociation and ionization reactions can cause high temperature real gas effects. The modelling of high-temperature real gas effects by different numerical methods can cause differences in the thermal physical parameters of the gas and thus introduce uncertainties into the flow field simulations. The ability of high-temperature real gas models to predict complex interference flows was investigated by computational fluid dynamics (CFD) and direct simulation Monte Carlo (DSMC) methods, using the example of double cone/wedge flows at high supersonic velocities. The results show that, unlike a calorically perfect gas, the thermochemical non-equilibrium process brings about changes in the thermodynamic properties and transport characteristics of the gas when real physical processes are considered. It also leads to changes in the flow structures such as shock angle, boundary layer thickness and separation zone dimensions. Therefore, attention should be paid to the correct application of numerical models in the study of hypersonic simulations.