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Meso-Scale Tearing Mechanism Analysis of Flexible Fabric Composite for stratospheric airship via Experiment and Numerical Simulation

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Journal of Shanghai Jiaotong university(Science) 2022年第6期27卷 873-884页

作者：陈永霖杨伟东谢炜程王晓亮付功义 School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China Aerospace System Engineering Shanghai Shanghai 201109China

stratospheric airships are controllable lighter-than-air aircraft and have great potential application in surveillance and *** envelopes,one of the main structures of a stratospheric airship,are generally made of flexible fabric composites to be lightweight,high strength,capable of containing lifting gas,and resistant to the harsh stratospheric *** composites,however,are prone to ***,their tearing behavior has attracted great *** paper explores the meso-scale tearing mechanism of an envelope and the temperature influence on its tear strength via experiment and numerical *** tear tests were conducted on cruciform specimens,which were contacted with liquids(cold alcohol or hot water)at different temperatures including-25,20,50,80℃.The specimens’tear stresses were measured and the meso-scale tearing behavior was captured with a ***,a novel finite element analysis model based on truss and spring elements was established to simulate the tearing *** was found that the simulation result has a relative agreement with the *** simulation results show that the maximum tear stress of the envelope drops by 39.62%as the temperature rises from-60℃ to 80℃ and the tensile properties of yarns and matrix account for stress concentration around a crack *** work deeply reveals the meso-scale tearing mechanism of the envelope and provides a valuable reference for exploring tearing properties of flexible fabric composites.

关键词： stratospheric airship fabric composite temperature tearing property numerical simulation

Light weight optimization of stratospheric airship envelope based on reliability analysis

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Chinese Journal of Aeronautics 2020年第10期33卷 2670-2678页

作者： Yunce ZHANG Yafei WANG Changguo WANG National Key Laboratory of Science and Technology for National Defence on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150001China Center for Composite Materials Harbin Institute of TechnologyHarbin 150001China

A stratospheric airship is an essential flight vehicle in the aviation *** this paper,optimal design approach of stratospheric airships is developed to optimize envelope shape considering three failure modes and multidisciplinary analysis models,and could also reduce the mass of a stratospheric airship to be deployed at a specific *** on a theoretical analysis,three failure modes of airships including bending wrinkling failure,hoop tearing failure and bending kink failure,are given to describe and illustrate the failure mechanism of stratospheric *** results show that the location,length and size of the local uniform load and the large fineness ratio are easier to lead to bending wrinkling failure and bending kink *** small fineness ratio and the increasing differential pressure are more prone to cause hoop tearing failure for an airship *** failure probability is sensitive to the wind *** an optimization design,the reliability analysis is essential to be carried out based on the safety of the *** solution in this study can provide economical design recommendations.

关键词： Failure modes Mass optimization Optimal design Reliability analysis stratospheric airship

Yaw controller design of stratospheric airship based on phase plane method

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Chinese Journal of Aeronautics 2016年第3期29卷 738-745页

作者： Miao Jinggang Zhou Jianghua Nie Ying Yang Xin Academy of Opto-Electronics Chinese Academy of ScienceBeijin 100094China University of Chinese Academy of Science Beijing 100049China

Recently, stratospheric airships prefer to employ a vectored tail rotor or differential main propellers for the yaw control, rather than the control surfaces like common low-altitude airship. The load capacity of vectored mechanism and propellers are always limited by the weight and strength, which bring challenges for the attitude controller. In this paper, the yaw channel of airship dynamics is firstly rewritten as a simplified two-order dynamics equation and the dynamic charac- teristics is analyzed with a phase plane method. Analysis shows that when ignoring damping, the yaw control channel is available to the minimum principle of Pontryagin for optimal control, which can obtain a Bang-Bang controller. But under this controller, the control output could he bouncing around the theoretical switch curve due to the presence of disturbance and damping, which makes adverse effects for the servo structure. Considering the structure requirements of actuators, a phase plane method controller is employed, with a dead zone surrounded by several phase switch curve. Thus, the controller outputs are limited to finite values. Finally, through the numerical simulation and actual flight experiment, the method is proved to be effective.

关键词： Attitude control Dynamics modeling Optimal control Phase plane method stratospheric airship

Change rules of a stratospheric airship's envelope shape during ascent process

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Chinese Journal of Aeronautics 2017年第2期30卷 752-758页

作者： Zhao Shuai Liu Dongxu Zhao Da Wu Gang Yin Shi Zhou Pan School of Aeronautic Science and Engineering Beihang University

stratospheric airship is a special near-space air vehicle,and has more advantages than other air vehicles,such as long endurance,strong survival ability,excellent resolution,low cost,and so on,which make it an ideal stratospheric *** is of great significance to choose a reasonable and effective way to launch a stratospheric airship to the space for both academic research and engineering *** this paper,the non-forming launch way is studied and the method of differential pressure gradient is used to study the change rules of the airship＇s envelope shape during the ascent *** simulation results show that the head of the envelope will maintain the inflatable shape and the envelope under the zero-pressure level will be compressed into a wide range of wrinkles during the ascent *** airship＇s envelope will expand with the ascent of the airship and the position of the zero-pressure level will move downward *** the same time,the envelope will gradually form a certain degree of stiffness under the action of the inner and external differential *** experimental results agree well with the analytical results,which shows that the non-forming launch way is effective and reliable,and the analytical method has exactness and feasibility.

关键词： Non-forming launch Pressure gradient stratospheric airship Wrinkles Zero-pressure level

The Constitutive Relation of a Fabric Membrane Composite for a stratospheric airship Envelope Based on Invariant Theory

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Computers, Materials & Continua 2017年第2期53卷 73-89页

作者： Junhui Meng Mingyun Lv College of Engineering China Agricultural UniversityBeijing 100083PR China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191PR China.

The study of stratospheric airships has become the focus in many countries in recent years,because of its potential applications in many *** and high strength envelopes are the keys to the design of stratospheric airships,as it directly determines the endurance flight performance and loading deformation characteristics of the airship.A typical envelope of any stratospheric airship is a coated-fabric material which is composed of a fiber layer and several functional membrane *** to composite structure,nonlinearity and viscoelasticity are the two main characteristics of such *** on the analysis on the interaction between the different components in the micro-mechanical model of the coated-fabric,several invariant values reflecting the characteristics of the envelope material are obtained according to invariant ***,the constitutive equation that describes the viscoelasticity of the envelope material is *** constitutive equation can represent both the individual roles of the warp and weft fibers,and their further coupled *** theoretical computation results were verified by off-axial tension *** results can help gain a deeper understanding of the mechanical mechanism and provide a reference for structural design of envelope material.

关键词： stratospheric airship fabric membrane composite constitutive relation invariant theory viscoelasticity.

Motion-pressure coupled control and simulation of long-endurance capability for multicapsule stratospheric airships

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Chinese Journal of Aeronautics 2024年第6期37卷 137-150页

作者： Zhiguang SHI Wei HUO Zongyu ZUO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Beijing Near Space airship Technology Development Co. LtdBeijing 100070China

The current study focuses on the motion-pressure coupled control for a multicapsule stratospheric airship and transforms the path-tracking and heading-hold control of airships into guidance tracking with a time-varying weighted sum of longitudinal and lateral velocities by the definition of compound ***,an improved nonlinear predictive control method is provided to reduce the control energy consumption by the rolling optimization of controller parameters based on finite time intervals,ensuring infinite-time path-tracking ***,combined with the proposed cyclic regulation process of safe pressure between internal and external capsules,this study can fully reflect the force-thermal coupled rule of airships under the actions of atmospheric environment and maneuvering force,while evaluating the long-endurance capability of airships under the conditions of safe superheating and *** effectiveness of the motionpressure coupled controller was verified through numerical simulations,which can overcome the influence of environmental wind and achieve a tracking effect for the desired cruise path and compound *** airspeed provided during the cyclic circadian time caused the maximum superheating of the helium controlled within 30*** helium in the internal and external capsules achieved circadian *** equivalent micropore diameter of the capsule of 5 mm can achieve 55 days of long-endurance *** controller satisfies the requirements of cruise-flight application modes for multicapsule stratospheric airships with important engineering value.

关键词： Compound speed Nonlinear predictive control Cyclic pressure regulation Long-endurance capability stratospheric airship

The Mechanical Characteristics and Experimental Study of the stratospheric airship

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Journal of Applied Mathematics and Physics 2021年第1期9卷 183-196页

作者： Xu Ning Ping Liu Zhihong Pan Jiangsu University of Science and Technology Zhenjiang China Southeast University Nanjing China

stratospheric airship is a special near-space air vehicle which has lots of advantages than other traditional flying aircrafts, such as long endurance, strong survival ability, low cost, excellent resolution detector etc. In addition, the stratospheric airship can be an ideal stratospheric bearing platform. This paper firstly gave an overview describing some technical differences between the stratospheric airship and the traditional airship, including the working environment, design specifications, structure characteristics, energy system, flying modes, and so on. Some technical difficulties including the materials, power system which apply to the stratospheric airship and deformation of the huge hull, super-heating effect, and station-keeping were discussed. Furthermore, technical target, technical specifications, design concept, and overview of flying tested about two stratospheric demonstration airships which were representative achievements of the research on the stratospheric airship in China were introduced. Finally, the predictions about the progress and direction of development were discussed.

关键词： stratospheric airship Demonstration Test Membrane Structure

Asymmetric error-constrained path-following control of a stratospheric airship

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Asymmetric error-constrained path-following control of a str...

Spatial adaptive integral LOS path following control for an under-actuated stratospheric airship

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作者： Tian Chen Ming Zhu Zewei Zheng School of Aeronautic Science and Engineering Beihang University The Seventh Research Division School of Automation Science and Electrical EngineeringBeihang University

This paper addresses the asymmetric error-constrained vector filed path-following problem of a stratospheric airship with external *** algorithm for asymmetric error-constrained path-following of the stratospheric airship is proposed based on the theories of asymmetric barrier Lyapunov function,vector field guidance and adaptive sliding mode ***,the asymmetric vector field guidance law（AVFGL） is presented,which can navigate the stratospheric airship along the predefined path and guarantee the tracking error is limited by aysmmetric error ***,an adaptive sliding mode attitude controller is introduced to track the desired attitude caculated by the ***,an adaptive velocity controller to maintain constant velocity is added to the control *** results demonstrate the effectiveness of the proposed control algorithm.

关键词： stratospheric airship Path Following Control Asymmetric Error Constraints Vector Field

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Spatial adaptive integral LOS path following control for an ...