Heuristic Deepening of the Variable Cycle Engine Model Based on an Improved Volumetric Dynamics Method

High-precision and real-time modeling are crucial for accelerating the research cycle of next-generation aero-engines. The volumetric dynamics method is acknowledged as the most accurate approach to capture the engine’s transition state process. Nevertheless, the traditional volumetric method encounters challenges, such as neglecting static pressure equilibrium within the mixer and complexities in ascertaining the component volume size when the dynamic simulation time step varies. To address these issues, an improved volumetric dynamics modeling method featuring pressure ratio collaborative updating and the adaptive virtual volume method has been proposed, and a real-time component-level model of a variable cycle engine is established based on this method. The pressure ratio collaborative updating method dynamically updates the pressure ratio of rotating components by inversely calculating the internal and external bypass pressure of the mixer according to static pressure equilibrium constraints and the momentum conservation principle. The adaptive virtual volume method determines the optimal virtual volume size using the particle swarm optimization algorithm, with cosine similarity serving as the evaluation metric. The simulation results indicate that the model based on an improved volumetric dynamics method achieves high accuracy and superior real-time performance. Moreover, compared to traditional modeling methods, the co-operating line of the improved volumetric dynamic method exhibits a smoother transition, signifying a closer resemblance to the real physical process.