Research of Variable Cycle Engine Modeling Technologies

A component level mathematical model of double bypass variable cycle engine (VCE) was built with a reference to the modeling method of two-spool-turbofan engine. The model of fan was developed with separated characteristic of fan tip and hub sections. The model of core drive fan stage (CDFS) model was built to work under single bypass mode and double bypass mode. The model was able to run as steady mode and transient mode. During the calculating process of the dynamic co-working equations, the method of volume dynamics was used in order to avoid the iterative calculations. In single bypass mode, it represents higher thrust and smaller bypass ratio, which is fit for the high-speed flight. In double bypass mode, it shows lower thrust and bigger bypass ratio, which is fit for the low-speed flight.