The similarity of oil/air two-phase flow in aero-engine bearing chambers was derived according to the basic theorems of thermodynamic and fluid dynamic firstly

the similarity criterion numbers such as Froude number

Euler number

Reynolds number

Prandtl number and Eckert number were obtained

then the model of aero-engine bearing chamber oil/air two-phase flow was built under multi-geometrical and operating conditions following the principle of system similarity. The oil/air two-phase flow fields of prototype and modeling bearing chambers were solved by numerical simulation

and the better consistency of flow fields dimensionless physical characteristic parameters

such as dimensionless tangential velocity

temperature and pressure between prototype and modeling bearing chambers

illustrates that the similarity criterion numbers and modeling method of aero-engine bearing chamber oil/air two-phase flow proposed are reliable. The proposal modeling method has certain reference value for guiding experiment design of bearing chamber oil/air two-phase flow as well as promoting the shift of theory investigation to engineering application of aeroengine lubrication system design.