An approach for zero-dimensional simulation of whole engine gas path was presented. By adopting modular modeling ideology

the transient engine performance model and air-system model were integrated and solved by means of dynamic data exchange. The corresponding modular simulation program was coded by utilizing object-oriented technology. A turbofan core engine was modeled to predict and analyze the dynamic changes of the air system bleeding and returning branches as well as their influences on the overall engine performance. Results show that the dynamic interaction between the main gas path and secondary air system exerts little influence on the overall performance of the aero-engine

but this influence is strong enough to cause significant imbalanced local responses of the secondary air system. This adverse impact should not be ignored in the design of modern high performance aero engine.