Study Of The Compilation Of Design Load Spectrum On Take-off And Landing Section Of Carrier-based Aircraft And The Aggravated Load Spectrum

As an important measure of aircraft carrier battle groups to dominate the ocean by the sky,carrierbased aircraft is an indispensable force of modern navy.Due to the constraints of deck geometry,aircraft carrier movement,air turbulence and other conditions,the catapult launch and arresting landing are taken by the carrier-based aircraft to complete the take-off and landing.In these processes,the load acting on the carrier-based aircraft is much higher than that on the ordinary land-based aircraft,and the load forms are not the same.The load spectrum designed and used by carrier-based aircraft is the basis for analysis and test of structural strength,damage tolerance and durability during the design of carrierbased aircraft.For the differences between loads acting on the carrier-based aircraft and the land-based aircraft,the method of compilating load-spectrum is also different.This paper studied virtual prototyping and the designed-used load spectrum of carrier-based aircraft’s catapult launch and the arresting landing,mainly includes the establishment and analysis of virtual prototyping,the study on carrier-based aircraft load spectrum compilation and the damage tolerance aggravated spectrum.Specific contents are as below:1.The method of load spectrum compilation based on the virtual prototyping is proposed for the first time,combined with the basic load spectrum compilation method-task analysis method,according to the commonly used method of load spectrum design,such as standard spectrum analysis,analogy analysis and flight simulation method.Besides,the application process and conditions of the method are analyzed.2.The complete virtual prototyping of carrier-based aircraft’s catapult launch and the arresting landing is established.The establishment is based on the analysis of the loads and constraints of the components in the carrier-based aircraft during the movement process.The determination methods to the ejection force,blocking resistance,aerodynamic force and other loads are studied.The automatic simulation method of multi working conditions based on the second way of Automation is adopted to realize the automatic establishment,analysis,calculation and data processing flow of large numbers of virtual prototyping working conditions.Meanwhile,the automation simulation software is completed.3.Based on the established virtual prototyping,two significant problems are studied in detail,namely,the dynamics problem based on the complete eccentric ejection process and the landing gear load affected by the landing parameters of carrier-based aircraft.The influence of eccentricity on each load during catapult launch and the influence of landing parameters on each load spectrum during the arresting landing are given qualitatively.4.A LHS-WF method for determining the typical landing condition is proposed.Based on this,a method for compiling the load spectrum of carrier-based aircraft landing is presented.In this paper,the global sensitivity analysis method of the landing variable to the landing load is studied quantitatively.At the same time,the paper studies the simplification of the sinking speed,the determination of the landing condition and the correction of the sampling range in the process of compilation,and combines the automatic simulation of multi working conditions to complete the compilation of load spectrum of certain type of carrier-based aircraft’s landing section.5.The measure of damage tolerance aggravated load spectrum is studied.The aggravation experiment of load spectrum is carried out by 26 pieces of test specimen used the damage tolerance load spectrum and the curve of crack initiation time and propagation time with the increasing coefficient is given.