Research On Mathematical Modeling Of Fault Prediction Of Aircraft Environmental Control System

As one of the key systems of airborne equipment,the aircraft environmental control system(ECS)will inevitably have various faults during operation,which will cause obstacles to the equipment operation and even cause serious accidents.In this paper,the mathematical modeling method of fault prediction of aircraft ECS is studied.First,based on many related domestic and foreign literatures,the development history,general situation and trend of aircraft ECS fault research have been sorted out,and the general method of ECS fault research also have been classified.Secondly,the mathematical model of each main component in a certain aircraft ECS system,such as heat exchanger,compressor,turbine and control valve,are established respectively,and validated by the experimental data.Based on the order of air flow in the system,the overall model of aircraft ECS,which is the basis for further study on the aircraft ECS failure prediction,is established by integrating the mathematical model of each component.The dynamic response of the each component outlet parameters and efficiency,when the system reaches steady state under the initial conditions,is analyzed.At the same time,the influence of ram air mass flow rate,temperature and engine bleed air temperature on system performance is also studied,and the performance curves of the system and components under healthy condition are obtained.Finally,based on the established model of aircraft ECS,the heat exchanger fouling and the turbine performance decay are taken as an example,and the aircraft ECS failure prediction model is finished.Meanwhile,the parameters of the various parameters of the system in the normal state to failure and the corresponding performance curves under different lifetimes of the system and components are also obtained.By comparing the performance curves in the normal state,the deviation of the system performance corresponding to the different positions of the life curve is identified,and the internal relationship between health status,residual life and performance deviations is established.