Study On Landing Cooling Characteristics Of Aircraft Braking System At High Plateau Airport

The high plateau airport has a special environment,high temperature and high altitude,which lead to the increase of the aircraft’s take-off and landing true speed,and the poor working conditions of the aircraft’s brake device.Its cooling characteristics and cooling time have an important impact on the quick turnaround of the aircraft.Using computer technology and mathematical analysis methods,this thesis selects the aircraft brake components as the research object to study the cooling characteristics of the braking system in high altitude airport landings.The main research contents and results of this thesis are as follows:(1)Based on the ANSYS simulation platform,the numerical simulation and verification of the transient temperature field of the brake pair are carried out.Taking the typical high plateau airport Lhasa Gonggar Airport as the background,and taking the main wheel brake pair of Boeing 737-700 as the research object,the temperature variation and heat dissipation of the brake pair under normal landing and interrupted takeoff conditions were analyzed,and the temperature variation of fuse plugs under different landing conditions was analyzed.The study found that the conditions of aircraft landing weight,starting braking speed,airport temperature,air pressure altitude and other conditions affect the braking energy,and braking energy is the main factor affecting the temperature distribution of the brake pair.It is mainly manifested in different landing states,the temperature cloud map and temperature curve of the brake pair are roughly the same,but the time and the maximum temperature value of the maximum temperature are different.The heat-up of fuse plugs is slow,and there is a certain time interval from the application of braking to the peak temperature of fuse plugs.(2)The data of the cooling time of the brake pair and the influencing factors(speed at the start of braking,landing weight,airport temperature,air pressure altitude)were collected and sorted by the orthogonal test method,and the range analysis was used to explore the influence of each factor on the target value and the primary and secondary influences.It is found that each factor has a significant impact on the target value,and the primary and secondary order of the factors affecting the cooling time of the brake pair is:speed at the start of braking>landing weight>airport temperature>air pressure altitude.The factors and target values were studied by unary linear regression analysis,nonlinear regression analysis,multiple linear regression analysis and BP neural network model respectively.The results show that the prediction effect of the BP neural network model is the best;Based on the BP neural network model,the trend analysis of the influence of various factors on the target value is carried out,which lays the foundation for the establishment of a typical high plateau airport quick turnaround braking cooling timetable.(3)Taking Lhasa Gonggar Airport,Jiuzhai Huanglong Airport,and Nyingchi Milin Airport as the background of three high plateau airport with relatively high passenger traffic,and based on the legal requirements of "Plateau Airport Operation",established the brake cooling timetable for quick turnaround at typical high altitude airports in my country.In order to improve work efficiency and reduce the error of table lookup through interpolation,a cooling time analysis software based on APP Designer was established.,and the functions and basic implementation methods of each module were expounded.Finally,the brake heat and its cooling method are analyzed.The research shows that the harsh high temperature environment of the brake pair during the braking process can be improved by enhancing the convective heat transfer capacity of the brake pair and texturing the surface of the brake pair.Prevent serious thermal damage problems.