In scramjet, the isolator plays a crucial role as a transitional component between the combustor and the inlet.SWithin the isolator, complex flow phenomena such as shock wave/boundary layer interactions, flow separation, and shock trains are observed under the influence of high backpressure from the combustor.SIn this study, the Self-Adaptive Turbulence Eddy Simulation (SATES) is used to numerically study the shock train characteristics in a cylindrical isolator. The primary focus is to analyze the potential challenges faced when the isolator is coupled with the combustor, including the effects of constant or pulsating backpressure at the isolator exit and wall temperature on the shock train characteristics within the isolator. The results indicate that an increase in the exit backpressure of the isolator, a decrease in the frequency of pulsating backpressure, and an elevation in wall temperature can all cause the shock train to move towards the inlet, leading to potential unstart risks. Therefore, in practical engineering applications, particular attention should be paid to the high backpressure and low-frequency oscillations induced during the combustor combustion process, as well as the wall heat conduction effects, to prevent the shock train from being expelled from the isolator, which could result in the shutdown of not only the isolator but also the entire engine.