Research On Aircraft Engine Modeling For Flight Simulation

Engine modeling is an important task of flight simulation. Accurate and efficient engine model helps to improve the accuracy and real-time of flight simulation. Meanwhile, the engine performance significantly affect the safety of aircraft takeoff. In order to design a suitable engine performance model for flight simulation, and to take this for analysis and research of civil aircraft take-off performance and take-off safety. Study work in this paper included:Based on the common characteristics of turbine engine, seleted JT9D engine as an example, established a steady-state performance model combining with data synthesis method and similar conversion methods, and a dynamic performance model using dynamic coefficient. Comparison of simulation and experimental data show that the model accuracy and efficiency are to meet the requirements of flight simulation.The typical constituent elements and basic description form of civil aircraft's aerodynamic characteristics are analyzed. Two-dimensional linear interpolation search algorithm was used to establish a B747-100 aircraft entire amount non-linear aerodynamic model.The take-off was divided into three phases which include roll, rotation, airborne and separately established take-off dynamic model considered the wind effect. The take-off dynamic model was integrated and interacted with the aerodynamic model, engine model, control law and atmospheric model, and used numerical integration method, achieved dynamic simulation and analysis for take-off and rejected takeoff in a variety of situations. By comparison of simulation and flight tests, efficiency and reliability of the model was verified.Combined with the definition of Federal Aviation Regulations, designed an integrated calculations and logical flow of civil aircraft takeoff performance, and designed a balanced optimization algorithm based on Newton Secant Method.Based on engine model and take-off dynamic model, studied the Assumed Temperature Thrust Reduction take-off and design the relevant parameters and simulation methods.The engine modeling study in this paper can provide solution for real-time flight simulation. Practical methods and conclusions in take-off performance study can be used as follow-up study and provide some reference.