In order to study the throttle characteristics of the precooled engine inlet before and after precooling

the two-dimensional axisymmetric inlet was used as the object

and the porous medium coupled source term method was used to conduct numerical simulation research. Under different working conditions

the precooling effect and the aerodynamic performance before and after precooling were compared. Studies indicated that when the mass-flow-ratio of turbine channel increased

the cone surface pressure of the subsonic diffuser section decreased

the area of the low-velocity zone decreased

the coefficients of total pressure recovery of both outlets showed a downward trend

and the precooling effect of the turbine channel was better. The total temperature of the outlet of the ramjet channel was also reduced by the influence of the precooler

and the degree of decline at high-velocity conditions was larger

but the degree of decline was not affected by the mass-flow-ratio of the turbine channel. In the high-velocity working condition of the same mass-flow-ratio of turbine channel

the turbine channel flow capacity was enhanced after precooling.