Based on the above-idle component-level model

a two-spool turbofan engine startup model was developed according to extrapolated component characteristics.The model can simulate the startup of windmilling and starter at high altitude.This model has taken into account the influence of fuel-air ratio on combustion efficiency

heat transfer model was built up to estimate the influence of heat transfer on combustor

thermal inertia of combustor and high-/low-pressure turbine as well as the change of total pressure recovery coefficients of different components during startup.The method of volume dynamic was used in order to avoid iterative calculations.The simulation results show that the real-time model has a simulated speed error less than 5%

making it possible to meet the demand of high-altitude startup performance simulation for aeroengine.